Understanding browser software, searches and inter
Web browser software
Web browser software is a program that allows access to webpages stored on the Internet. A web browser allows the user to find information on websites and webpages quickly, it does this by using:
- key word searches
Unifrom Resource Locator is a web address. One of the ways of accessing a website is to type the URK into a web browser.
Key Word Searches
If you want information about a topic but don't have the URLs of any websites, then you can type key workds into the search box on the web browser.
Understanding browser software, searches and inter
Links are often called hyperlinks, by clicking on them the user moves to another place on the same webpage, a different webpage on the same site or a webpage on a completely different site. You can also link to files such as a presentation file,
Menus offer the user a series of selections that they make by clicking on one of them. The menus can use text or you can use images, usually with some ecplanation on them.
Search for and search on webpages
Searching for information is performed using a search engine such a google. The search results are displayed on the basis of relevance or who has paid the most money to get in the top results. Clicking on a search result takes you to a website and may take you straight to the website. It may then be necessary to perform a search of the content of the website.
Understanding browser software, searches and inter
Making Comparisons of Websites
When creating your own website make sure you consider the following:
- House style- websites need to convey an image that reflects the organization. It needs to fit in with other material produced by the organization such a brochures, business cards, adverts etc.
- Audience- you need to know what your main audience will be and tailor the content, look and navigation to suit them
- Size- you need to consider the number of pages.
- Techniques used
- online forms (e.g. feedback)
- emails (can send emails to the organization)
- quizzes (e.g. used to give feedback)
- questionnaire (e.g. used to ask user their opinion about website, products)
- games (e.g. educational games, advertising games)
Tools&Techniques for creating websites
Master pages/templates provide a quick way of creating webpages. They supply to structure for the website and the navigation that is used to move around the site. They act as a framework for the website and all the developer has to go is fill in their own content. They are ideal for people who need to develop websites quickly and have no design or website development skills
The home page is the main webpage of a website for a person, business or organization. It is the page most users will arrive at and is therefore the starting page of a website. It is important that the most important information is located on this page along with the ways a user can navigate to the other pages in the website.
When users search for info using a search engine they are presented with a list of results. Experiments conducted to see where users looked on a results page showed that they tended to concentrate on a triangular area of the screen called the golden triangle. This means it is really important, if you are producing a website that you want to be viewed by a lot of people, that your website appears in the golden triangle when it is searched for.
Tools&Techniques for creating websites 2
Hotspots are an image or piece of text used as a link of a webpage. When you click on the image or text, you are taken to another part of the same page, a different page or a different site, or it may open a new file or a new window.
A rollover button/image is a button/image that changed its appearance when a cursor is moved over it.
These are links that are formed using various shapes
Back and Forward
Overviews and sitemaps are forms of navigation. They allow a user to see exactly what is included on the site and to move around the site without having to use the normal navigation on the webpages. Sitemaps can be a graphical map or text-based. A text-based sitemap is sometimes called a table of contents
Tools&Techniques for creating websites 3
Bookmarks are used to keep a record of a webpage that you find interesting. The bookmark records the web address with a title in a list that you can display at any time.
If a webpages is long, you can use an anchor link that allows a user to jump to the section of content they are interested in. This saves a user having to read all the content they are not interested in to get to the part they want.
Leader boards and banners
A web banner is a rectangular area on a website that displays advertisements and also acts as a link to the advertiser's site. Banners come in all sizes but one popular-sized banner is called a leader board and it is 728 pixels long by 90 pixels wide.
Web icons are small pictures on websites that enable users to do certain things when clicked on. Web icons should clearly display what it does.
Tools&Techniques for creating websites 4
HTML (HyperText Markup Language)
HTML is the special code that is used for making webpages. HTML consists of special markers called tags that tell the computer what to do with the text that is entered. HTML is a text file, like Word except that it contains tags. Tags tell the computer how to display the text or format the page. IT IS NOT A PROGRAMMING LANGUAGE
Web browsers contain a toolbar called a navigation bar, containing buttons that you use to move around the site and perform certain actions. These buttons would include:
- back or forward
- key work search
Tools&Techniques for creating websites 5
Coloured pixels are produced by mixing different amounts of the colours, red green and blue (RGB). Mixing light is not the same. You can get white light when you mix red, green and blue light, you would not get white if you mix the same paint. The amounts of red, green and blue are expressed as numbers, which range from 0 to 255. The numbers are usually represented as hexadecimal numbers.
Hosting of websites and uploading times
- Hosting of websites- A web server is a computer that contains the information that users of the Internet can access using their web browser. A web server needs to be permanently connected to the internet so that all users are able to access the information. Web servers for internet service providers contain many websites.
- Uploading times- The uploading time is the time it takes to take a website that has been produced on a computer and then transfer it over a network to a web server. Uploading time depends on the resolution of images used, if the page contains animations or movies, the complexity of the design, the number of webpages and the amount of content
Tools&Techniques for creating websites 6
Advantages of webpages and webpage features
- Makes the info available to a huge number of people
- Enables anyone who has access to the internet to be able to access the information
- Uses multimedia features to make the site interesting to users.
Disadvantages of webpages and webpage features
- Some features such as flash movies can take time to load, this can put off users from using the site
- People who do not have access to the internet are at a huge disadvantage
- Some of the features such as links to movies, may not be accessible to those users who do not have a fast broadband connection.
Tools&Techniques for Creating Slide Presentations
A design template is an outline design providing a basic colour scheme, font type, font size, etc. You then do not need to worry about the design, so you can concentrate fully on the content of each slide (text, graphics, video, sound, etc.)
Animation involves getting some of the content that makes up the slides to move. The simplest way of including animation is to use animation provided by the presentation software. This allows you to select certain animations for the way the material such as headings and bullet points are added to a slide. Animation is classified as follows:
Another way of including animation would be to include clip art that is animated or to produce a flash animation and include it on the slide.
Tools&Techniques for Creating Slide Presentations
Transitions and Timings
The movement from one slide to another is called a slide transition. To make your presentation more interesting you can:
- alter the way the slide appears on the screen
- alter the speed at which the slide appears
- get the computer to make a sound during transition
When a slide presentation is self-running it is important to leave enough time for you audience to read what is on each slide. Using the software, you can alter the timings for each slide.
Most people think of clip art sites as just containing ready-made images but many of them contain sound as well. Sounds and music can liven up a multimedia product but they need to be used with care as they can detract from the message or content being delivered. As well as clip art libraries, you can use websites as sources of sound files.
Tools&Techniques for Creating Slide Presentations
There is sound and movement and you can add so much more interest than simply writing about the same thing or looking at a still picture. There are two main ways of obtaining video for use in presentations&video:
- by creating the video yourself using a digital video recorder
- by using video created by someone else
You can use a search engine such as yahoo to search for video in a similar way to the way you search for images. There are sites such as Youtube that are huge sources of video and it is possible to link to these sites from websites and presentations
Rather than having bits of paper with prompts written down on them, it is better to have them with the slides. You can see these notes with the slides but the audience only sees the slides. These notes may also be useful to your audience, so they can be printed out at the end along with the slides.
Tools&Techniques for Creating Slide Presentations
Navigation: hyperlinks and hotspots
Navigation: Navigation is the way provided by the software for a user to choose which slide they want to view next. Remember that it is possible for a presentation to be interactive just like a website.
Hyperlinks: A hyperlink is an icon, graphic or word on a document that, when clicked with a mouse, opens another slide or webpage.
As well as using text for hyperlinks, you can create images that contain links. Images containing links are called graphical hyperlinks, although you will often hear them referred to as hotspots. You can create your own buttons and turn them into hotspots or you can use an image. It is important that you tell the user that the image is a hotspot. Sometimes you want to have an image that contain several hotspots. An example of this could be a map where the towns or main tourist areas on the map are the hotspots. When a user moves over a town or area, the cursor changes to a hand indicating a hotspot and when they click on it, they are taken to a different page containing information on that town or area.
Tools&Techniques for Creating Slide Presentations
Narration is speech that is recorded about each slide. Narration is useful if the speaker is not present when the presentation is viewed. In order to record a narration there needs to be a microphone connected, Most laptop computer have a microphone built in but with desktop computers, you will need to connect one. Before starting the narration for each slide, it is a good idea to write down a script. You can then refine this script and read from it when recording the narration.
When presentations are given to an audience by a speeker it is usual for the speak to give out copies of the slides to the audience. This enables them to take notes and refer to the material in the future. There are several different printing formats for slides:
- You can have 1,2,3,4,6 or 9 slides on each page
- You can print an outline view that lists what is on each slide in the presentation
Advantages of Presentation Software
- The use of presentation software makes the presenter look more professional
- It encourages the presenter to summarize what they are saying into a number of bullet points
- The presenter can print out the slides so the audience have some information to take away and digest
- The presenter is able to make use of full multimedia capability in their presentation
- Presentations can be stored and transferred to people who were unable to attend the presentation
- Presentations can be shown using a projector, whiteboard or TV or on a desktop or laptop computer screen, so the presenter has flexibility in the way the presentation is delivered.
- There is the presenter notes facility that gives a set of notes on screen that the audience cannot see in case the presenter wonder what to say next
Disadvantages of Presentation Software
- The files for presentations containing video are very large and need a lot of memory and storage for them to run successfully
- The audience can get fed up seeing all these special effects that people tend to put in their presentations
- Good presentations can take a long time to set up
- Sometimes people concentrate more time on presenting the information than they do on the gathering of the information in the first place. This means that the information is sometimes incorrect
- Sometimes the sound effects and animation used in presentations can annoy the audience
What is Multimedia?
Multimedia mean many media such as text, audio, still images, animation, video and interactivity. Usually multimedia means more media that just text and graphics, so this means that a normal book or magazine would not be considered multimedia.
It is possible to have books and magazines on the internet and these usually make use of multimedia features such as video, sound, etc.
Multimedia in Education
People learn in different ways, so teachers like to have variety in the way they teach. This is why most educators think that multimedia is a good thing, because it offers so many different ways to get a message across.
Reading aa book to learn a language is not ideal as you need to hear how words sound. This is why many schools have material on iPods and other MP3 players so that students can listen to lessons when they are doing other things such as walking to school.
If you are able to access a computer then you can have learning packages that make use of animations and video as well as sound. You can also have interactive links to interesting webpages.
Uses of multimedia in education include:
- interactive whiteboards to help with teaching and learning
- online tutorials
- simulations to explain how things work
- revision material
Multimedia in Entertainment
The internet has made some big changes in the way we entertain ourselves. More and more people are using the internet to entertain themselves by posting text, images and video on social networking sites. They are also using webcams to chat to each other.
There has also been a huge change in the way people listen to music, with people turning to downloads rather than physical CDs. In addition may people do not want just to listen to the music, they want to see video of the music being played. Television programmes are also being viewed on the Internet. There is a growing trend to actually stream the music, video, films, etc., over the internet, which means that the person does not have to waste time downloading them. You are likely to start getting the ability to view films and TV programmes on iPods and similar devices.
This means you will not have to download films and music as you simply select them on the device and the file will be streamed to your portable device of computer.
Multimedia in Business
There are many different ways multimedia is used to business such as:
- websites to promote products and services
- presentations given to an audience of either your own staff or customers
- promotional videos/cartoons
- banner adverts on other organizations' websites
- adverts on the internet
Multimedia in Society
The main benefits of multimedia to society are:
- Flexibility- there are so many different ways to do the same thing using multimedia. For example, you could read a story yourself, you could download it and listen to someone reading it on an MP3 player, you could watch a video of someone reading it or perhaps watch it as an animation.
- Interactivity- the user has more control over what material they want to see, listen to ,etc.
- Integration of Material- this can be used to make the material easier to understand. This make it easy to get a message across as it can be done in so many different ways.
- Attention getting- the word gets around quickly using websites.
The use of multimedia is set to increase with the use of:
- e-books- a wafer thin device that can store hundreds of books
- streaming content such as TV programmes straight to people's portable devices or computers
- internet access all the time from portable devices.
The Importance of Memory Size
Having a large amount of memory is important. Having more memory means:
- applications run faster on their own
- more applications are able to run at the same time
- you are able to move quickly between applications
It is always important to know about the size of certain files because it is essential if you want to know how many of them could be stored on a particular storage device.
File Size- Here are the file sizes from the smallest to the biggest:
The Importance of Memory Size 2
The demand made by multimedia software on memory
Multimedia software demands a lot from the hardware of the computer. It is constantly driving the specification of an average computer higher. This means that computers need more powerful processors can creating multimedia products such as websites means that many different applications and files need to be open at the same time.
Backing Store Needed for Multimedia
Backing storage is storage that is not the main memory. It is therefore storage on:
- magnetic hard drives (fixed or portable)
- optical disks (e.g., CD-ROM, DVD)
- flash drives (sometimes called pen drives, memory sticks, etc.)
- memory cards
Multimedia software makes use of a large number of pieces of hardware.
Screens are sometimes called monitors or VDUs (visual display units). Here are some facts about screens:
- The come in lots of sizes
- They are usually in colour
- They are useful for enquiries
Both desktop and laptop computers use TFT(thin film transistor)/LCD(liquid crystal display) flat panel screens. The advantages of TFT/LCD scrrens are:
- They are light- hence their use in laptop computers
- They are cheaper to run because they consume less power
- In the case of desktop computer systems- they do not take up very much desk space
Plasma screens- are large flat panel screens and are generally available in larger sizes compared to TFT/LCD screens. They have the following uses in ICT:
- used in reception areas
- used in videoconferencing systems
- used for presentations to a large audience.
Screen size and resolution
The screen size is usually determined by the type of application the multimedia is for. For example, although it is usually desirable to have a large screen for viewing video, this may not be possible, as the device may need to be portable. Resolution is measured in pixels per cm or inch. The greater this value, then the higher the screen resolution and the clearer the image on the screen will appear.
MIDI (Musical Instrument Digital Interface) Instruments
MIDI is an interface, which means, a way of connecting and getting two devices to communicate with each other. MIDI can send signals to electronic devices such as keyboards, music synthesizers, guitars and drum machines. These devices can also send the signals back to the computer hardware so that the signals can be stored and modified in some way. For example, the sound from a drum might be too loud in a recording. Using MIDI you could save the sound from the frum whilst keeping the loudness of the other instruments the same.
Input devices are those hardware devices that input either instructions or data into the computer for processing. Here are the main hardware devices used with multimedia systems.
The main points about a mouse are:
- Mice are input devices because they are used to issue instructions by making selections
- When the mouse is moved, a pointer or cursor moves on the screen mirroring the movement of the mouse
- Selections can be made by pressing the mouse buttons.
- A scroll wheel can be used for scrolling through long documents or viewing images in detail
- A mouse may also be used for drawing lines, sizing graphic objects such as pictures or clip art.
A graphics tablet consists of pen-like device that you use to draw or write on a tablet (it looks a bit like a flat board) an it then appears on the computer screen. You can use a graphics tablet to design your own graphics. Some graphics tablets contain special buttons to select shapes or special pictures.
Touch sensitive input devices
To operate a touch screen you simply touch the item on the screen to make a selection or produce a drawing. Usually a special pen-type device, called a stylus, is used to create drawings or edit existing images. Most creative people find it much easier to draw using a stylus rather that a mouse.
A microphone allows sound to be converted into data. Using a microphone allows you to do the following:
- you can record sounds/music
- you can have a narration to a presentation, which save you having to speak
- you can tell the computer what to do
- you can dictate letters and other documents directly into your word-processor or email package. This is called voice recognition.
Digital Still Camera
A digital camera looks like an ordinary camera except there is no film and there is usually a screen on which to view the picture (called an image) when taken. Here are some facts about digital cameras:
- Digital cameras have memory where they store the image
- The more memory a camera has, the more pictures you can store.
- There are no developing fees as with an ordinary camera
- If the picture is not suitable then it can be taken again
- You can transfer the pictures to your computer, where you can store and edit them
- Digital cameras are more expensive than ordinary cameras
Digital cameras produce an image made up of millions of dots. The greater the number of dots (called pixels) in the same space, the clearer the picture will appear. This is called the resolution of the image. High resolution images use more dots and take up more storage space on the computer.
Digital Video Camera&Web Cameras (Webcams)
Digital video cameras look the same as ordinary video cameras except that they store the image digitally. Here are some other facts:
- Most digital video cameras can capture still as well as moving images.
- Images may be stored and edited on the computer
- You can use video in websites.
Web Cameras (Webcams)
A webcam is simply a digital camera that is used to capture still images and video images. These images can then be transmitted to a computer where they are stored in a suitable graphics format. If required, pictures can be used on a website
Key Word Serches
You simply type a word, series of words or a sentence and the multimedia package will find relevant content.
It is fairly easy to create quizzes on websites or quizzes using presentation software such as PowerPoint. Both types of multimedia software use the interactive features of the software to jump from the questions to the answers. Quizzes can be included to find out how much a user has learnt from using a multimedia product. They can also be used to assess how much a person already knows about a subject.
People who design websites like to get user feedback, so one way of doing this is to get users to complete an online questionnaire. This is a very cheap way of finding out what users think of the site, or their online shopping experience in the case of an e-commerce site. As the answers to the questionnaires are completed, the results from all the questionnaires can be processed and analysed.
Interactive Components 2
Games are normally at the forefront of multimedia technology and are popular with all generations. The demands that games software makes on computer hardware are high, which results in people having much more up-to-date systems at home than they do at work.
Many multimedia products, such as presentations and websites, use links to enable a user to take them to information stored in a different file or on a different website.
Advantages in Using Multimedia Software
The advantages of multimedia include:
- Offers interaction with the user- they can decide what they want to do and in which order.
- Offers different ways of presenting information other than just reading text and looking at still images.
- Can suit different learning styles. For example, people who do not like reading can use animations or listen to audio.
- It enables learning through exploration, discovery and experience.
- It is very time consuming to produce a good piece of multimedia software and this can make some software expensive
- It places high demands on the hardware- so you often need to upgrade or buy new computers
- Sometimes when you print a webpage the text is not formatted properly
- Multimedia uses lots of power and this make the battery run down faster on laptops+ other portable devices
- It may not be accessible to certain groups of people who do not have high spec computers and broadband internet
- Playing computer games is mainly a solitary activity&this is bad for children who can be addicted
Techniques for Storing Text, Images, Sound and Vid
Text is best prepared using word-processing software and then imported into the multimedia software. This is because there are many editing features in word-processing software. There are 2 ways in which you can put the text into the multimedia package, you can:
- save the word-processed file and then import it into the multimedia software
- copy the text in the word processing package and past it into the multimedia software.
Images can be obtained from many different sources, you can:
- scan old photographs or pages from books
- copy and paste an image from a document or a webpage
- copy and save an image
- obtain files of images from photograph or clip art libraries
- take digital images yourself and save them
- create images using software
Techniques for Storing Text, Images, Sound and Vid
Sound is either embedded or not embedded. Embedded means that it is stored with the multimedia software when you save the software. Non-embedded means that there is a link to the sound file. This means that if the multimedia file is copied to a different computer then the sound file may not always be copied at the same time.
Vector and Bitmap Graphical Techniques
Bitmap images are made up of millions of pixels. Normally there are many pixels and they are extremely small. This means you cannot see them in an image. If the image is enlarges, then you can start to see the pixels and the image appears blocky. The more pixels an image contains, the greater the file size needed to store it.
- Bitmaps are big files so they take lots of space on a disk. They also take a long time to upload or download.
- They can lose their sharpness when they are enlarged or reduced in size
- They are made up of individual pixels that can be set to a colour
- They are used for photographs or images with continuous colours.
Vector&Bitmap Graphics 2
Vector graphics are graphics that use maths to work out the positions and lengths of lines, curves, etc. Vector images:
- can be enlarged or reduced keeping their sharpness
- do not take up much space when stored compared to bitmap images
- are made up of objects that can be edited and filled with colour
- are used for more precise images such as: maps, technical drawings/plans or images that contain a limited number of colours (e.g. logos, clip art, lettering)
- are not good for re-creating photographic type artwork
- are uploaded and downloaded faster owing to their smaller file size.
The advantages of vector graphics over bitmapped graphics
- Vector graphics have very small size. Small file size means that it does not take long for it to load
- They have a low upload and download time and so are ideal for the web
- they are much easier to edit and can be resized without any loss in quality
- by using software it is easy to zoom in and out on a vector image.
Vector&Bitmap Graphics 3
The number of pixels per inch or pixels per centimetre determines the screen resolution. The more pixels per inch or cm then the better the resolution of the screen and the better the picture it can produce. If a screen has a screen resolution of 300 pixels per inch then by knowing the size of the image in pixels we can work out how big it will appear on the screen.
Pixel dimensions are the horizontal and vertical measurements of an image expressed in pixels.
The benefits and problems in resizing images
- You can fit the image into you design
- You can alter the shape slightly
- In the case of bitmap images they become blurred when resized
- If the image is too big, you may not be able o fit it on the screen without scrolling
Vector&Bitmap Graphics 4
Memory requirements for different backgrounds
Many pieces of clip art have a transparent background. The more complex the background in terms of variety of colours used, then the more memory is needed to store it. In order of increasing memory for backgrounds to images we have:
Manipulating Graphics Using Standard Tools
- Zoom: Allows a user to magnify or reduce the size of an image on the screen. Usually zoom is used to magnify an image so that the individual pixels can be viewed and edited if necessary.
- Selection: Allows the whole of a graphic or just part of the image to be selected for editing
- Transforming: There are a number of ways you can transform an image. For example, you can rotate or reflect
- Sizing: The graphic will have been pre-stored at a certain size but it can have its size altered to fit any space available. This process is called sizing
- Scaling: Scaling is sizing to a certain pre-determined size. Often this is expressed as a percentage of the original size of the graphic.
- Copying: An invitation to a Christmas party could be set on paper covered by graphics of Father Christmas. The quickest way to do this would be to import one of them and copy the rest into the various positions.
- Cloning: A clone is simply a replica of an original graphic.
- Brush Settings: In most graphics editing packages there is a tool called the paintbrush and when you click on it you will see various options appear in the options selection. Controlling a paintbrush on a screen by moving a mouse is quite difficult and some professional artists prefer to use an alternative input device such as a light pen or a graphics tablet.
- Layering: If a graphic consists of lots of smaller graphics then you can draw each small graphic on its own layer. When all the layers are placed over each other, the complete graphic is produced. It is easier to edit graphics and re-use them if they're on their own layer.
Colour Effects&Imaging Effects
Any element of a graphic can be produced in a colour using a palette of colours.
Gradient tools allow the colour to be more intense in one area and then start to fade away as you move away from this area. Backgrounds to slides in a PowerPoint presentation can have a gradient applied.
- Altering the pixels in a photographic image/air brushing- it is possible to zoom into a bitmap image until you can see the individual pixels. It is then possible to edit the pixels by changing their colour. You can therefore remove skin blemishes, unwanted objects and even people from an image
- Removing red eye from a photograph- this is a common problem in photographs taken using a flash. It is easily removed using graphics software.
Transparency Effects& Composite Patterning
Transparency involves taking an image and putting it on whatever background is used for the page. It can also be used when you want to see what is behind an image.
Composite patterning means a pattern that can be repeated over and over. Composite patterning can be used:
- for backgrounds
- to fill shapes.
GIF stands for graphical interchange format and along with the file format called JPEG, it is one of the two main file formats for images used on the Internet. GIF files have the advantage that hey are small in size. The original image file is compressed by removing any irrelevant data in the file. The main disadvatnage with GIF files is that only 256 colours are used even though an actual image can contain 16 million colours. This means that GIF images do not quite look the same as the original image.
- Uses 8 bis for colour
- Maximum of 256 colours
- Uses compression
- Used for Simple graphics
GIF files are good for:
- images on the web
- photographs on the web
JPEG stands for Joint Photographic Expert Group. With GIF, it is the main file format for images on the Web. JPEG is ideal for photographs and many digital camera automatically create files with the file format. Like GIP, JPEG compresses the original image. There is a slight distortion when the image is converted to a JPEG file. his is noticeable at the edges of the image. JPEG files use 16 million colours, which is why they are ideal for photographic images.
- Uses 24 bits for colour
- Maximum of 16.7 million colours
- Use compression
- Used for images with continuous colour e.g.photos
PNG Files,TIFF Files&PSD Files
PNG stands for portable network graphics. PNG files used compression that creates a compressed image without any loss in image quality. It uses 16 million colours but the resulting file size is slightly larger than GIF or JPEG files. When you create a graphic using the software Fireworks, you create it in this file format. You can then choose to save the file in different file formats depending on the use to which the graphic is to be put.
TIFF stands for Tagged Image File Format. TIFF is a bitmapped image format and is ideally suited to scanned images, images with continuous colours and photographs. TIFFs are widely used and can be easily modified and can have any number of colours
PSD stands for Photoshop Document. Photoshop is a popular piece of software used for creating and modifying images. PSD file format produces very high quality images but as there is no compression, the file sizes are large. This means that if you used PSD files with the Internet they would take a while to upload and download.
BMP Files&ESP Files
This file format saves the image as a map of pixels. It supports millions of colours but because of the very large file size the time taken to load the file from the internet is large. Pictures created using the package Windows Paint are saves as bmp files and of course digital photographs can be stored as bmp files.
ESP stands for Encapsulated PostScript and is a standard format for importing and exporting PostScript files. ESP files can contain, text, graphics and images and contain a small preview image. Adobe Photoshop can save bitmap images in this file format.
Animation processes are those steps that need to be taken in order to produce an animation that could be as simple as a moving image or logo to a full length movie.
Persistence of Vision Technique
The human eye sees an image for one twenty fifth of a second after the image has actually disappeared. This means that it is easy to produce animations that do not appear jerky. A serious of frames can be produced with each frame slightly different, so that the objects appear to move. Joining them up at a certain rate means that the eye sees a smooth transition from one frame to the next.
Flip books are books containing drawings, with a slightly different drawing on each page,m that appear to move when the pages are flipped quickly. The persistence of vision gives the appearance of smooth movement.
This technique uses very sophisticated and expensive software, which means that it is mainly used by film studios for the production of films. As well as the special software, you also need to use modelling techniques to make the whole thing look realistic. These modelling techniques use shade and textures just like in real life.
Stop Motion Animation
In this type of animation a model is photographed again and so on. The photographs are combined an dthe tiny movements are joined together to show the model moving smoothly. It is a slow and laborious process but it is simple o do and a good way to get into animation.
Flash/Key Frame Animation
Lots of websites use flash to produce impressive results. Flash is a piece of software used to create interacive and animated websites. Flash has 3 advantages:
- Flash images are very fast to load
- You can create interactive animated images using flash
- You do not need to know anything about programming to use it
Key frames are the starting frame and the finishing frame in an animation. When you use flash, when you want an object to move across the screen you need only to define the key frames where something changes. You can leave it to flash to put in the frames between. This is tweening, it reduces you work load considerably.
Film Making&Special Effect Industries
Illusions to illustrate a film, programme, game or other computer program used to stimulate the imagination are called special effects. With the use of digital cameras and video editing software, special effects are fairly easy to make.
In the olden days of films, special effects included the use of props, scale models and atmospheric effects such as rain, wind and snow. Nowadays with the use of computers and digital imagery, special effects can be made that are much more convincing and much cheaper to produce.
Uses of Animation in VLEs+Websites &Animations for
Animation is used in educational multimedia products from programs to teach young children to read and do very basic maths to material for A-level.
Animations for Websites
Adding animations to a webpage can make the webpage more interesting but you have to make sure that the images are appropriate for the content. One quick way of adding animations to a webpage is to use an animated gif.
Identification Through Logos
Most organisations and companies use logos to help present an image to customers. If these logos are on paper, such as in brochures, letterheads, business cards and so on, it is impossible to use animation. However, many organisations have a website or produce presentations, so it is now possible to bring the logos to life and animate them.
Uses of Animation in VLEs+Websites &Animations for
Standard Banners for Webpages/Leader Boards
A web banner is a form of advertising that is seen on websites.The banners are adverts embedded into a webpage. If you click on one of these banners, you are taken to the website. There is a link between the banner and the advertiser's website. Banners come in a variety of different sizes. When designing webpages it is a good idea to use one of these sizes, as you may want to have advertising on your site and you need to leave spaces for these.
The Advantages&Disadvantages of Animation in Comme
- It can help explain a difficult concept
- It can be used to entertain young children
- It can attract users to a website
- It can make learning fun for young children
- Good animation can be expensive to produce
- It can distract users away from the content or the message being given
- On a website, it can take a while to load, which can put off some visitors to the website
Planning an Animation
Taking time to plan an animation is very important. Here are some of the things you need to do when creating an animation:
A folder tree is a graphic representation of a hierarchical folder structure. With any project in IT it is very important to get organized before you start by thinking about the folder structure you are going to use and about the folders in folder structure. Being organized by creating a folder tree at the start does take time but you will reap the benefits later on because all the files will be easy to find. It is also much easier to back up the folders and files.
Explaining how an animation multimedia presentation or website will work is quite difficult. It is not easy explaining the visual ideas involved. Storyboarding provides a way of communicating visual ideas. A storyboard is a series of sketches showing the layout of drawing, still photographs or animations involved in a multimedia presentation or website. Storyboards are used to show the sequence and layout of ideas.
Storyboards: What Should a Storyboard Contain?
There are no rules as to what a storyboard should or should not contain. You are completely free to use your artistic talents. Typically, a storyboard for a website or presentation would contain:
- Rough designs showing what the menus will look like
- What pictures are included
- In an animation it can show some of the frames
- What video is used
- What sound is included
- Some detail of the text to be included.
Awareness of Audience
An animation should always be chosen or designed with the audience in mind. An animation like by one group of people pay be disliked by another group. You also should take care in the choice of music you use to go with the animation.
A mood board is a compilation of elements that will give the look and a feel of the animation, website or multimedia product. It can include such things as examples of proposed types of animation, colour palettes used, patterns, font styles for text etc.
The main purpose of the mood board is to prevent the designer putting lots of work into a design that the client does not like. The mood board is quick to create and allows a design to be discussed and altered.
In an animation each unique image used in the animation is called a frame. The frame rate is the frequency or rate at which the frames appear on the screen. The greater the frame rate, the better the quality of the movement of items in the animation. Low frame rates result in the image flickering.
Looping: By drawing say 8 slightly different images and looping so that they go back to the beginning it appears that the image is moving.
Awareness of Audience 2
There are two types of animation: vector and bitmap animation.
In vector animation the motion is controlled by vectors rather than pixels. Mathematical equations are used to draw the frames in their new positions. Adobe flash produces vector animation
In bitmap animation the arrangement of bits on the screen changes in some way and a new bitmap is produced. Advantages of vector animation over bitmap animation:
- The animation is cleaner
- The animation is smoother
Claymation is a form of stop animation. It uses an object made of a substance that is easily moulded. A model is made and it is photographed and then the model is altered slightly and photographed again. The process is repeated until a whole series of frames are produced and then these frames are played back producing the animation. Producing a whole animation using this techniques involves a huge amount of work and time.
If you enlarge a bitmap image too much then you start to see the individual pixels that make up the image. Sometimes pixelation is added deliberately.
In this animation technique a piece of film with the movement of live actors is drawn over so you get an animation effect with realistic movement. Once the outline of the moving actor has been captured an artist can fill in the rest of the image.
Tweening is sometimes called inbetweening. This is because you create a start frame and a final frame and the computer generates all the inbetween frames so that the start image changes into the final image. Adobe Flash is a software package that many people use for animation and this package allows tweening. It allows you to specify how an object is to move or change during the tweening process.
Onion skinning is a technique used in animation where several frames in an animation are superimposed over each other. If you look at the picture of the horse shown on the right, you can see the current frame as well as the previous three frames. The reason this is done is to allow the animator to keep track of the motion so they have a better idea when they create the next frame.
Grouping- grouping images is often done so that they are treated as a single image rather than separate ones. This makes i easier to move and size hem.
Backdrop- this is the scenery against which the characters in the animation appear. For example, an animation of a talking cat might have the contents of a room as the backdrop.
Cloning- often in animation you need several items of the same thing. Rather than create each one from scratch, it is easier to create one and then copy it. The copies are identical and are called clones.
File Formats&Their Adv and Dis
- widespread use of format on the internet
- ideal for simple images
CGM (computer graphic megafile)-CGM is a file format for 2D graphics that can be represened in binary or one of two types of text. It is a series of instructions that explain how to draw the graphic and is therefore used to produce vector graphics.It can be used with any system.
PNG (portable network graphics)
- PNG was a replacement for GIF
- It offers more features than a GIF
- It offers more compression than GIF
- Older web browsers do not support some of the features of PNG
Sound Storage Devices&Sound Cards
MP3 is a file format used to compress CD-quality music to about a tenth of the file size compared to a normal CD. One minute of music takes about one megabyte of storage capacity. Once the music has been downloaded from a site, it may be stored on a hard disk. It could hen be copied onto a CD using a CD writer and this is where the problems start. Although some of the music that you can downloaded off the internet can be copyright free, the majority of the material is copyright. This means that you are not allowed to copy or distribute it without the permission of the copyright owner.
As MP3 files are compressed to normal sound files, it means that about 14 hours of music can be stored on a single CD.
A sound card is an electronic circuit board containing chips and other components and circuitry that enables high quality sound to e produced. Most people use their computer to produce sound, so all computers have a sound card installed. However, people do replace these with more expensive cards that are able to produce higher quality sound.
Microphone: A microphone allows sound to be converted into data. Special software called voice recognition software is used to interpret the sounds into words. A microphone allows you to:
- You can tell the computer what to do
- You can dictate letters and other documents directly into your word-processor or email package, this is called voice recognition
- You will need a microphone if you want to send voice mail or take part in videoconferencing
- You can record a live music performance
MIDI (Musical Instrument Digital Interface)
MIDI enables a computer and a musical instrument to communicate with each other. For example, when a keyboard is played the music is transferred using MIDI to the computer where it can be edited if needed and stored. The MIDI converts the music in analogue format from a musical instrument into a digital format that the computer can manipulate and store.
This process can be reversed by the music stored on the computer being fed back and using MIDI it can play the music back on the keyboard or other instrument.
Sound is a continuous wave and is therefore analogue. As computers can only work with digital data, it is necessary to convert the analogue data to digital data. This process is called analogue to digital conversion. Once the data is in digital format, the computer can store it, edit it, transfer it to another computer and play it back.
Loudspeakers and headphones used analogue signals, so when these devices are used to output sound from the computer, the digital data/signal from the computer has to be changed to an analogue signal. This is done using a digital to analogue converter.
Sequencers (Multi track recording studios): Sequencers are hardware or software used to create and manage electronic music. Examples:
- Drum machines- these are electronic musical instruments that simulate the sound of a drum and sometimes other percussion instruments. Drum machines are sequencers because they create and manage the drum beats.
- Music Workstations- a single piece of electronic equipment that allows a musician to create electronic music. Music workstations consist of the usual computer but with a large screen with all the controls such as knobs, sliders, buttons and sampling information. Some music workstations make use of touch screens.
Notators (Music composition software) : A notator is a piece of software that allows you to compose your own music and you do this by entering notes into the computer via: the keyboard, a MIDI systems, or scanning a piece of music on paper using a scanner.
Once the notes are entered into the systems, the musician can experiment by changing notes, loudness, tempo etc. The main advantage is that the notator allows the musician to experiment. The notator can also be used to create the music for individual musical instruments that can then be played together to produce the final piece of music.
Creating Music 2
Sound Wave Editors
Sound wave editors are software that allows the editing of sound waves. Using the software sound waves can:
- be edited
- be cut, copied and pasted
- have effect like echo, amplification and noise reduction spread.
Sound wave editors can also be used to alter a person's speech pattern, so it can be used to disguise a person's voice or even simulate another person's voice. This is often used on the news so when a witness or victim speaks they can not be identified.
File Formats For Music
There are a lot of file formats to choose from if you want to store and play sound:
wav- This file format retains every bit of audio information, which means that when you play it back, it will sound exactly the same as when it was created. This is perfect if you want the highest quality sound but the file sizes needed to store the files are very large. This means you wouldn't be able to store many tracks on a portable player and if you download them it will take a lot longer.
MP3- This is the best known format and the most popular. It uses compression so the files are only about one tenth of the size compared to a wav file or a music file on CD. This eans you can store around 10 times the amount of music in the same space. The quality is still very good but not as good as with wav format. MP3 files need to be decoded when used, which means they are not as fast to load.
wma-wma stands for Windows Media Audio and is a file format used with windows that offers high quality sound at high compression. This enables music files to be decoded, stored and distributed quickly.
Downloads have become popular owing to:
- the ease with which they can be obtained
- the ability to just download tracks that you want- you do not need to purchase the whole album
- you can still burn the tracks to a CD provided they are only for personal use
- the ease with which they can be loaded onto portable players such as iPod's, MP3 players and mobile phones.
There are a number of problems with downloads including:
- Many people use file sharing sites to avoid having to pay for downloaded music tracks
- People who downloaded music or films illegally could be cut off from the internet by their internet service providers
- You do no have a physical CD that can be sold at a car boot sale or on Ebay
There are copyright problems with sounds and music in the same way as there are with text and images. Here is some advice:
- You cannot use music on a website without the copyright owner's permission
- Do not copy samples of voices or sounds without permission
- Do not make copies of music tracks to share with your friends
- Do not use illegal file sharing sites as your use of the internet may be affected
All sound and music is produced by someone and this person hast o make a living. All sound and music is protected by the copyright, designs and patent act 1988.
What is a Network?
A network is two or more computers that are linked together so that they are able to share resources. These resources could be a printer, scanner software or even a connection to the internet. You can also share data using a network.
Peer-to-Peer and Client-Server Networks
- Each computer on the network has equal status
- All computers can share each other's resources
- They are only suitable for small networks with fewer than ten users
- Only very basic knowledge is needed to set one up and use it
- As more people use the network the whole network slows down considerably
- One more powerful computer, called the server, is used to store the data and the programs needed by the whole network. The server is in control of the network
- Software and data is stored on the server, so it can be accessed by all the computers on the network.
- The network is totally dependent on the server.
- They are the popular choice for networks that need lots of computers.
LAN (Local Area Network):
- Confined to a small area
- Usually located in a single building
- Uses, cable, wireless, infrared and microwave links that are usually owned by the organization
- Cheap to run and build
WAN (Wide Area Network):
- Cover a wide geographical area (e.g. between cities, countries and even continents)
- In lots of different buildings, cities, countries etc.
- Uses more expensive telecommunication links that are supplied by telecommunication companies
- Expensive to build and run
The devices in a network may be arranged in different ways. Each way is called a topology. It is important to note that in a wired network the topology would show how the wires are connected. However, may networks are now set up without wires, making use of radio, infrared or satellite links. The topologies in this case will show the communication links between the devices. There are 3 main topologies:
Ring Topology 2
This is a ring network that is also a peer-to-peer network because there is no server. With the ring topology: All the computers are arranged in a circle, Data send by one computer passes around the ring until it reaches the correct computer.
- It is easy to add extra device,
- each computer has the same access as the others so no one computer can 'hog' the network.
- If there is a break in the connection (wire or wireless) then the whole network fails,
- Faults are difficult to locate,
- It is impossible to keep the network running whilst equipment is added or removed because there is only one path for the data to follow.
Bus Topology 2
All the devices connected to the network are connected to a common shared cable called the backbone. Signals are passed in either direction along the backbone.
- They are cost effective because of the small amount of cable needed
- Simple cable runs makes them easy to install
- It is easy to add extra devices to the network
- If more than about 12 devices are connected to the network, then the performance of the network is poor
- If there is a break in the backbone cable, then the network cannot be used.
Star Topology 2
The star topology uses a central connection point for all the devices on the network. The central connection point can be a serve, or inexpensive devices called hubs, routers or switches.
- They are fault tolerant- if one of the cables fails, then the other computers can still be used
- They are load tolerant- extra computers can be added without much loss in performance because all computers have their own path to the hub/router/switch/server
- It is easy to add extra computers- extra computers can be added without disturbing the network
- Higher cost- the large amount of cabling needed makes it a more expensive topology
- Dependence on the central hub/switch/router/server- if the device at the centre of the network fails, then the whole network will fail
The Internet, Intranets and Extranets
Internet- The internet is a huge group of networks joined together. Each of these networks consists of lots of smaller networks. This means that the internet consists of hardware.
Intranet- a private network that uses the same technology as that used by the internet for the sending of messages/data around a network. The main use of an intranet is to share organizational information and share resources
Extranets- an intranet is restricted to employees of the organization, whereas with an extranet, customers, suppliers and other partners as well as the employees of the organization can access the information. Extranets are not accessible by the general public and this is ensured by the use of usernames and passwords.
Hardware&Software Needed for Data Transfer
Data Transfer Medium
Data transfer medium is the material through which data travels from one computer to another in a network. For small, simple networks this is usually wire, but may networks work wirelessly. Wires add considerably to the cost of a network, especially the cost of installing them. The main forms of data transfer media are:
- metal wires
- fibre optic cable
Network Cards-Before a computer can be connected to a network, it will need to have a network card. Most modern computers have these when you buy the computer.
Network Software- Small networks can be run using existing Windows software. For larger client server networks, specialist network operating systems software is needed. This software includes facilities to:
- keep track of the software being run on each computer
- keep all the applications software up to date
- check that all computers have and are kept up to date with the latest virus checker
- check that a user has not loaded software illegally onto their computer
- check what hardware each computer has (e.g. processor, memory, size of hard drive etc.)
Hardware&Software Needed for Data Transfer 2
Hubs, Switches and Routers
Hubs- are simple devices used to join computers in a network so they are able to share files&an internet connection
Switches- are like hubs in that they are used to join computers in a network but they are more intelligent. Switches look at each packet of data and then send it to the computer it was intended for. This reduces the amount of data travelling around the network and makes it work faster.
Routers- are devices that join several wired or wireless networks together. They are often used in the home to enable several computers access the internet using a single connection
Bridges- are devices that connect separate LANs together to form one large LAN.
Connecting Networks Together
Many networks are connected together. For example, you might have a couple of computers networked together in the home, that share a connection to the internet using a router. You therefore have a small network connected to the largest network in the world (the internet).
Connecting LANs and WANs together using a gateway
Often a LAN is connected to a WAN. For example, the LAN might be located at the head office of an organization with lots of computers in small branches around the country. To connect a LAN to a WAN a device called a gateway is needed and this allows a computer in the LAN to communicate with a computer in the WAN and vice versa.
Advantages of Network Systems
The advantages of network systems compared to stand-alone computers:
- You can share hardware- you can just have one printer and one scanner, as any of the computer connected to the network can use them
- Software can be installed in one place- you do not need to install software on each computer. This makes it faster to install and easier to maintain. If the software needs to be upgraded, then this is much easier if only one copy is used.
- Improved security- work can be saved on the network. The network manager will make sure that the work is backed up. Passwords make sure that other people cannot access your work unless you want them to.
- Speed- it is very quick to copy and transfer files
- Cost- when software is bought, the school can buy network versions. These are much cheaper than buying a copy for each stand-alone computer.
- Email facilities- any user of the network will be able to communicate using electronic mail. This will be much more efficient compared to paper-based documents such as memos, etc.
- Access to a central store of data- users will have access to centrally stored data.
Disadvantages of Network Systems
- A network manager will need to be employed- this can be quite expensive
- Security problems- a virus could get onto the system and cause problems, or hackers may gain access to the data on the network.
- Breakdown problems- if the network breaks down, users will not have access to the important information held.
- Expensive- a server and cables and/or other communication devices will be needed. The installation costs of a network are also high.
Integrated Point of Sale (PoS) Systems
Point of sale terminals are where you pay for your goods in a store. PoS terminals are networked together. This means when an item is sold and it bar code is scanned, the system looks up the price and description details to print out an itemized receipt. At the same time the system will deduct the item from stock so that the stock control system is updated. PoS terminals consist of the following hardware:
- Bar code readers/laser scanner- this is used to input a number that is coded in the bar code as a series of light and dark lines
- Keyboard- the keyboard is used to enter codes on items if the bar code is damaged
- Touch Screen- these are often used in restaurants where there are no goods to scan.
- Swipe card readers- these are often used in restaurants where there are no goods to scan
- Chip and Pin readers- these are used by customers to insert their credit/debit cards containing a chip. The systems then asks them to enter their PIN (personal identification number), this proves to the system that they are the genuine owner of the card
Point of Sale terminals are connected via networks to other systems such as:
- Payment systems- where the customer can pay using credit/debit card
- Loyalty card systems- where customer are given loyalty points according to how much they spend.
- Accounts systems- where the money coming into the shop is accounted for
- Automatic stock control systems- the system knows what has been sold, so that it can automatically reorder more once the stock falls below a certain amount.
Automatic Stock Control
When an item is sold at the PoS terminal the number of that particular item in stock is reduced by one. This means that the computer knows how many items are in stock. Once the number of itms has fallen below a certain level, the computer system will automatically order more stock from the supplier. This means that stores should not run out of fast-selling items.
Good stock control systems are very important in supermarkets as customers will go elsewhere if the shop keeps running out of key items such as bread, milk, etc.
The Function of an Operating Systems
Operating Systems are programs that control the hardware directly. The operating system supplies the step by step instruction that tell the computer hardware what to do. Functions:
- Manage and control any devices such as printers, scanners, webcams etc.
- Provide a user interface that makes it easy for the user to load programs, search for files, copy files etc.
- Hide the complexity of the hardware from the user
- Deal with any errors that occur while the computer is working on tasks
- Provide the interface between the application packages being run and the hardware
- Allow new hardware or software to be installed using installation programs
- Contain various utilities such as disk formatter, virus checker, encryption etc.
- Handle the storage of data by keeping track of all the files and directories/folders on the disk drives
- Maximize by the use of computer memory by the operating system deciding where in the memory the program instructions are placed
- Recognize new hardware such as a pen drive, camera, portable hard drive, etc. has been attached to the computer and load the software needed to control it
- Organize resources when the computer user is running several programs at the same time
Brands of OS software: MS windows, Macintosh OS-X, LINIX, linux
The Features&Uses of Different Types of User Inter
An interface is where two things meet, so a user interface in ICT is the point where the human user meets or interacts with the ICT system. This is commonly called the user interface or sometimes the human-computer interface (HCI).
The different user interfaces and their features
Cursors, prompts, icons, menus etc. allow you to get things done with your computer. They are all part of your user interface. A user interface can make your computer either hard pr easy to use. You will probably have experience software that is frustrating to use. There are 3 main types of user interface:
- Command Line/Driven Interface- here you have to type in a series of commands. This type of interface is very hard to use.
- Menu-Driven interface- here you are presented with a list of things to do and you have to choose one of them by typing in either a number or a letter. These are easy to use but are limited in the sorts of things you can do with them
- Graphical User Interface (GUI)- these are very easy to use and have all the features such as windows, icons, menus, pointers, etc.
The Features&Uses of Different Types of User Inter
Graphical User Interfaces and WIMP
Graphical user interfaces (GUIs) are very popular because they are easy to use. Instead of typing in commands, you enter tem by pointing and clicking at objects on the screen. Microsoft Windows and Macintosh operating systems are gaphical user interfaces. The main features of a GUI are:
- Windows- the screen is divided into areas called windows. Windows are useful if you need to work on several tasks.
- Icons- these are small pictures used to represent commands, files or windows. By moving the pointer and clicking, you can carry out a command or open a window. You can also position any icon anywhere on your desktop
- Menus- menus allow a user to make selections from a list. Menus can be pop-up or pull-down and this means they do not clutter the desktop whilst they are not being used.
- Pointers- this is the little arrow that appears when using Windows. The pointer changes shape in different applications. It changes to an 'I' shape when using word-processing software. A mouse can be used to move the pointer around the screen
The Features&Uses of Different Types of User Inter
Office assistants are features of GUIs and they provide assistance or help when a user want to do something using the software. When the office assistant is asked for, the system tells them how to complete the task.
Used to: explain how to use the computer, show the new features of a new version of the software
There are many ways you can customize the desktop environment, such as:
- You can alter the size of the icons
- You can alter the way the mouse works
- You can alter resolution, brightness and contrast on the computer screen
Voice Driven Applications&Menu/Dialogue Boxes
Voice driven applications, also called voice recognition, can be used to:
- issue commands to the software
- enter data into the software
Voice driven is a popular interface because manufacturers are trying to make devices small, but if there is a small keyboard, then it is hard to use.
A dialogue box is a window used with a graphic user interface (GUI) that displays a message to the user or requests that a user types in some information it needs. It is called a dialogue box because there is a constant interaction between the user and the computer. Sometimes the dialogue box simply informs the user about something such as the printer running out of paper and the user only has to acknowledge they have seen the information and click on OK to get rid of the box.
Touch Sensitive Applications
Touch screens enable the device to be kept small but the screen can still be almost the same size as the device, as a keyboard is no longer needed. You use your fingers to interact with the interface. You will have seen this type of interface used in some mobile phones such as the Apple Iphone.
Windows 7 provides a touch screen interface that can be easier to use than a keyboard and mouse. Many devices used by the general public have touch screen interfaces and these include:
- portable music players
- mobile phones
- information kiosks
- notebook computers
- point of sale systems in supermarkets and restaurants
- learning aids
Biometrics make use of the features of the human body that are unique to a particular person. Usually this is a person't fingerprint or the pattern on the back of the eye.
Rather than have to log-in a computer by providing a username and a password, a user can now simply put their finger into a scanner. The system automatically recognizes who it is that is using the computer and gives them the network resources allocated to them.
There is also a biometric method that can identify a person from behind by the way they walk. This is a new method and can be used for access to control for buildings and can help police catch criminals who think they cannot be identified from behind.
Adv&Dis of each type of HCI
Advantages of a command line interface:
- Quicker- in some instances you can do a task more quickly by typing a command line rather than using the mouse and all the features of windows
Disadvantages of a command line interface:
- Very difficult for beginners to use-you have to learn the structure(called the syntax) of commands
- You have to remember the instructions/commands you need to do a particular task
Advantages of GUIs
- No language needed
- Use of icons- novice users can simply select programs or things they want to do
- Easier to use a mouse- most users would prefer to use a mouse to point&click
Disadvantages of GUIs
- More memory is needed- sophisticated GUIs have large memory requirements
- Increased processing requirements- faster&more powerful processors are needed to run the latest GUIs
Advantages of E-commerce Systems
E-commerce means using the Internet to conduct business. When you buy a CD, DVD or book off a website you are involved in e-commerce. Advantages to customers
- Ability to order goods 24/7
- Greater choice of goods from a global marketplace
- No travelling needed as goods are ordered from home
- Allows disabled people to do their own shopping
- Cost savings are passed to customers with cheaper goods.
Advantages to businesses
- Running costs of an e-commerce business are much less than having shop premises
- Online catalogues are more easily updated
- Fewer staff needed
- Ability to reach customers at any time of the day
- Global marketplace means customers from around the world can shop
- Fluid pricing- easy to change prices from day to day
Disadvantages of E-commerce Systems
Disadvantages to customers
- Problems with fraudulent sites
- Sometimes more hassle when returning goods
- Harder to assess the quality of goods before ordering
- Loss of the social pleasure of shopping
- Hidden costs of postage or duties e.g. VAT
- Customers worried about security of credit/debit card details
Disadvantages to businesses
- Network downtime can be very expensive
- Cost of delivery may make goods more expensive
- Reliance on third party delivery companies who may be unreliable
- Increased competition from abroad offering cheaper goods
Data capture is how the data gets into the system. E-commerce systems use the customer to enter data. They allow the customer to select items to put in the virtual trolley (shopping basket) and then go to the checkout where they enter their personal details. These are entered into an online form using the keyboard. They are then connected to a secure site where they enter their payment details such as credit/debit card number.
Checking is by performing a visual check. This involes the customer checking carefully all the details they have entered. There are also validation checks on many of the fields on the online form that the customer uses to enter their details. There are presence checks to ensure important fields are not left blank.
Type of Processing
Real times (transaction) processing is used. This means that the transactions are process as they occur (i.e when customers place orders). It is important that processing takes place as soon as details are entered so that the goods or services can be reserved for that customer.
Output from the System
Once an order has been entered the system will automatically acknowledge receipt of the order by sending the customer a copy of the order by email. This will also show that payment has been made. Order confirmations can be output on screen or pointed out.
Banking- Cheque Clearing Using Magnetic Ink Charac
Cheque clearing uses input methods that use magnetic characters printed on the cheque. With MICR, the numbers are printed onto the cheque in a special magnetic ink, which can be read at very high speed by the magnetic ink character reader. Most of the data are pre-printed onto the cheque but the amount is not known until the person writes the cheque. When the cheque is presented for payment, the amount the cheque is for is then printed onto the cheque. again in magnetic ink.All the cheques are batched together at a centre operated by all the banks called a clearing centre. All the cheques are read and processed in one go by the machine, so this is an example of batch processing. Advantages:
- Accuracy- the documents are read with 100% accuracy
- Difficult to forger-because of the sophisticated magnetic ink technology used, it would be difficult to forge cheques.
- Can be read easily- cheques are often folded, crumpled up, etc. Methods such as OCR or OMR would not work with these. MICR uses a magnetic pattern, so this is unaffected by crumpling.
- Speed of reading- documents can be read at very high speed&this is particularly important for the clearing of cheques
- Expensive- the high-speed MICR character readers are very expensive.
Automatic Teller Machines (ATMs), commonly known as cash points are the 'hole in the wall' cash dispensers that many people use when the bank is not open or when they do not want to queue inside the branch. In order for you to use the service the machine needs to check that you are the card holder. You are asked to enter a PIN that only you should know. If the card is stolen then the thief should have no way of finding this. Things you can do with an ATM:
- You can get cash out
- You can find out the balance in your account
- You can change your PIN
- You can make deposits
- You can obtain a mini statement listing your recent transactions
Types of Processing Used with ATMs
Real time transaction processing is used with ATMs. This means that as soon as a customer gets the money out of their account, their balance is updated. This only takes a short amount of time but is not real-time processing because real-time processing takes place instantly.
Benefits to banks in using ATMs:
- Staff are freed from performing routine transactions so that more profitable sales oriented work can be done
- Fewer staff are needed, since the computer does much of the routine work
- A 24 hour per day service is provided to satisfy their customers' demands
- The system makes it impossible for a customer to withdraw funds from their account unless they have the money in their account or an agreed overdraft
Benefits to Customers:
- Some customers prefer the anonymous nature of the machine since it cannot think you have stolen the cheque book or think that you are spending too much
- It is possible to use the service 24 hours per day: ideal for those people who work irregular hours
- It is possible to park near the dispenser of an evening, so getting cash is a lot quicker
- Fewer queues, since the transactions performed by the ATM are a lot faster.
Banking- Online Banking
Many of the tasks you would have had gone to a bank branch to do, you can now perform at home using Internet or online banking. Using online banking you can:
- view bank statements
- transfer money between accounts
- make payments for bills
- apply for loans
Online banking uses the Internet to enable a customer at home to connect to the bank ICT systems and interact with them. In order to do his the customer has to enter log-in details and answer some other security questions. Any details passed between the bank and their customers are encrypted to ensure hackers cannot access banking details
Banking- Backup Systems
Most large organizations operate 24&, so their systems must be capable of running continuously. Main points:
- Backups are normally taken remotely
- Many systems use dual computer systems- so if one breaks down, the other one takes over.
- Uninterruptible power supplies are used to power the ICT systems, which means there will not be a problem with power cuts.
What is a Payroll?
Payroll is an application that deals with all the information needed to pay employees. Not all employess get the same pay, even if they are doing identical jobs. Some may be given more pay because they have worked longer in the organization. Some people's pay may differ because the amounts deducted vary. This depends on a person's tax code, which in turn is determined by an individual's circumstances. Each employee is supplied with a detailed breakdown of the amount they are paid, including deductions, in the form of a payslip.
In addition to the money paid to employees, an organization has to send money to many other organizations such as he HM Revenue and Customs for income ax and National Insurance contributions, pension agencies for the payment of pension contributions, trade unions for the payment of subscriptions and so on.
Because of the security and cost problems of dealing with the transfer of large amounts of cash, many organizations use electronic funds transfer (EFT) to transfer the money between the organization's bank account and the employees' accounts. They can also use the system to make payments of income tax and National Insurance contributions that have been deducted from employees' pay.
Data Capture, Checking&Type of Processing
There are lots of ways in which data is captured and these include:
- Employees clock in and clock out using a card or key- this records the hours they have worked and these are input into the computer directly.
- Employees fill in timesheets that are read automatically- sometimes these use techniques such as OMR where the employee shades in boxes on a form. Other methods use OCR where the reader is able to read numbers and letters the employee fills in on a form.
- Employees fill in timesheets that are input manually using a keyboard.
Processing timesheets- Both types of form can be collected and batched together to be read automatically at the end of the week or month. They are then input into the computer, which processes them is one go. This type of processing is called batch processing
Checking- When forms are processed, it is important that every timesheet is processed. Batch totals and hash totals are used to ensure that all the forms are processed
Output from a payroll system- After the pay has been calculated a document called a payslip is printed. As most payrolls are processed in a batch, the payslips are also printed in a batch. The payslip provide confirmation of the hours worked, the pay, the tax, National insurance and other deductions and the net pay. These are provided so that the employee is able to check them.
Modern Mail Handling Methods
Mail merge letters target individual potential customers and these can be produced using word processing software.
People in organization receive huge amounts of email each day and it takes time to sort. Much of the email is advertising goods or services that have not been asked for.
Luckily email software is able to identify this type of email and can place all the spam email in a separate folder. The user can then quickly glance at the emails to check none have been trapped by the spam filter by mistake. They can then be deleted.
The importance of feedback
A computer can be used to control a robot arm. If we want the robot arm to move through a certain angle, we can give an instruction to a special motor that moves small steps at a time. When the command has been issued, the arm will move to the required position. If there is an object in the way of the arm, it will stop. The problem is that if his happens, it will assume that it has reached its desired position. The computer can no longer be sure of its position.
What is needed is a way for the arm to relay its actual position back to the computer. It can do this by making use of sensors. The sensors continually send data about the position of the arm back to the computer. If the robot arm is not in the correct position then remedial action can be taken to put it in the correct position. Here, output from the system directly affects the input. Such a system is said to use feedback.
Example of Process Control Making Use of Feedback
1) The computer issues a control signal to the motorized tap instructing it to turn the tap on and let the water into the container
2) As the water enters and the level rises, the water pressure is continually fed back to the computer
3)As soon as the pressure reaches a certain value the water is up to the correct level. A control signal is sent back to the tap to turn the water off. At the same time a signal is fed back to the computer from the temperature sensor. If the temperature of the water is less than 80 degrees, a control signal is sent to the heater to turn it on
4) The temperature is continually measured and sent back to the computer, which compares the temperature with its set level (i.e. 80 degrees). As soon as the temperature reaches this level, a control is issued to the heater to turn it off. At any time the temperature drops below 80 degrees, the heater is witched on again so that the temperature remain constant at 80 degrees.
The Type of Processing Used for Process Control
Process control always uses real-time processing because the system needs to react instantly to changes so that the system being controlled is safe.
What is Bionics?
Bionics is where you apply biological methods and systems found in nature to the study and design of robots and computers.
What is a Robot?
A robot is a device that can be programmed to perform a sequence of actions. Robots can be re-programmed with a new set of instructions so that they are able to carry out a completely different task. For example, a robot arm can be programmed to hold equipment for welding and the same robot arm holding a different tool can be re-programes to spray cars with paint.
Sometimes the programs are entered into the computer directly and in other cases, such as paint spraying, an experienced operator will guide the robot through the actions it needs to take. It will then remember these actions so that is can perform the task on its own.
Advantages of using Robots:
- No time taken off sick and robots do not take holidays
- Possibility of robots working 24/7
- Ensures consistency in the quality of the job
- Robots do not need paying
- Robots are able to carry out boring or dangerous jobs
Problems caused by robots
Robots in factories do not replace people; however, people are needed to build program and repair them.
What is Artificial Intelligence?
Artificial intelligence is a reasoning process performed by computers that allows the computer to:
- draw deductions
- produce new information
- modify rules or write new rules
The computer, just like a human, is able to learn as it stores more and more data.
What is an Expert System?
An expert system is an ICT system that uses artificial intelligence to make decisions based on data supplied in the form of answers to questions. This means that the system is able to respond in the way that a human expert in the field would come to a conclusion. A good expert system is on that can match the performance of a human expert in the field. The three components of an expert system:
- Knowledge base- a huge organized set of knowledge about a particular subject. It contains facts and also judgmental knowledge, which gives it the ability to make a good guess, like a human expert.
- Inference engine- a set of rules on which to base decisions and mos of these rules have the 'if then' structure. It is the part of the expert system that does that does the reasoning by manipulating and using the knowledge in the knowledge base.
- User interface- the user interface present questions and information to the operator and also receives answers from the operator
Uses for Expert Systems
- For making a medical diagnosis or giving medical advice
- Used by oil companies for deciding where is the most likely place to find oil
- For giving tax advice to individuals and companies
Adv&Dis of Expert Systems
- Fewer mistakes- human experts may forget but expert systems don't
- Less time to train- it is easy to copy an expert system but it takes many years to train a human expert
- Cheaper- it is cheaper to use an expert system rather than a human expert
- Lack common sense- humans have common sense so they are able to decide whether an answer is sensible or ridiculous. Human experts can make judgements based on their life experiences, and not just on a limited set of rules as in the case of computers.
- Lack sense- the expert system can only react to information entered by the use. Human experts have many senses that they can use to make judgements. For example, a person describing a type of pain might use body language as well that would not be detected by an expert system
Protecting a Network
Encryption is used to protect data from prying eyes by scrambling daa as it travels over the internet. Encryption is also used when saving personal data onto laptops or removable storage devices. If any of these gets lost or stolen then the data cannot be read. Encryption should be used for:
- sending credit card details such as card numbers, expiry dates, etc. over the internet
- online banking
- sending payment details
- confidential emails
- sending data between terminals where confidentiality is essential
- storing sensitive personal information on laptops and portable devices and media
Identifying the user to the system:usernames
A username is series of characters that is used to identify a certain user to the network. The person who looks after the network will use this to allocate space on the network for the user. It is also used by the network to give the user access to certain files.
The network manager can also keep track of what files each user is accessing for security reasons.
Preventing Unauthorized Access to the System: the
A password is a string of characters that the user selects. Only the user will know what the password is. When the user enters the password, it will not be shown on the screen. Only on entry of the correct password will the user be allowed access to the networks.
When transactions are performed on the computer, there may not be any paperwork to go with the system. So that the system can be audited, the software produced will have a function built in that provides an audit trail. The audit trail provides evidence of what has happened in the system. Transaction logs are a deterrent to people who might be thinking of committing computer fraud, as they will know they are likely to be found out. It also provides evidence for the police to prosecute computer fraudsters.
Firewalls are software, hardware or both used to filter out unauthorized requests from outside users to gain access to a network. This keeps hackers out. Firewalls also filter data so that only allowable data is allowed into the systems. All networks that have access to the internet should have a firewall.
File Access Rights
Access rights restrict a user's access to only those files they need in order to perform their job. Their rights are initially allocated to them by the network manager and when they log on, by giving their username/user ID and password, these rights are allocated by the computer.
A user can have a number of different levels of access to files including:
- Read only- a user can only read the contents of the file. They cannot alter or delete the data.
- Read/Write- a user can read the data held in the file and can alter the data
- Append- they can add new records but they will be unable to alter or delete existing records
- No access- they cannot open the file so cannot do anything to it
Physical protection is all the types of protection that involves the use of actual devices or media to ensure the security of the data held. For example, having key pads on doors to computer rooms to prevent unauthorized access is physical protection. Methods of physical protection:
- Attaching computers to desks to prevent them from being stolen
- Keyboard locks to prevent keyboards being used
- Locking backups away in fireproof safes
- Using biometric devices such as retinal scanning, fingerprint scanning to gain access to rooms
Physical Protection coninued
Backups are copies of data and program files kept for security reasons. Should the originals be destroyed then the backups can be used. Using a file server and storing both programs and data in it, means that backups can be taken in one place. Backups should be held on removable devices or media that are taken off site each day. The individual users do not need to take their own backups. The person in charge of the network will take the backups needed.
Many systems now take backups automatically at a certain time of the day and send the data using the internet to a company that specialize in storing backups.