AS I.C.T

Data: is raw facts and figures that have no meaning on their own. 

Information:is data that has been given a meaning and put into context and processed by a computer.

Knowledge: is a set of rules that is applied to information in order to manipulate the information.

Example: 19071996 is data as it means nothing on it's own. But this gets turned into information such as a birthday - the 19/07/1996. Then a set of rules (knowledge) gets applied, such as this person is 16 years old so would be interested in discounted textbooks and stationary as they are in school. 

There are two different ways that we can get data - Direct Capture and Indirect Capture.

Direct data capture is when specific data is collected for a specific purpose, then the data would be entered into a computer and processed. For example, on a cesus form or on a tax return.

Indirect data capture is when data is collected directly but then its passed on to another company and used for a different purpose. For example the data could be personal contact details for a membership to a gym but this information could then be passed onto a sports shop who could send the person advert leaflets for sport equipment. 

The data cycle is the overall process of information being converted into data. 

Data is entered at the input satge. - (1)information is converted into data before it is input, (2) the data may be converted into coded form, (3) the data is input and validated to make sure it had been read correctly. 

The Data is processed by the computer - (1)The data is compared to a database of items. (2) Data from the database is read and stored temporarily in RAM. (3) the data in the database is updates and checked. (4) The data stored in RAM is processed.

The Processed data is output - (1) The results are communicated to the user, (2) the results may be stored permanently, (3) The information obtained at the output stage might be then used as feedback to input more data.  

Data can be coded for example, male and female may become M and F which can be inputted into the database. 

Advantages of coding

• Less memory needed to store the data.
• Quicker and more convenient to enter a code.
• Data entries can be validated more easily.
• Coded information can be more private, especially for sensitive information.

Disadvantages of coding:

• May be difficult to remember the codes
• Accuracy may be lost
• Some codes are difficult to understand.

Good quality is data that is accurate, up to date, complete and relevant 

Accurate: If data that has been collected is inaccurate then the information that will be produced will also be inaccurate which can also mislead the company.For example, if the prices in a supermarket aren't accurate on the till system then the till assistant will have to keep changing the prices and may be undercharging or overcharging the customers.

Up to date: If the data isn't up to date then the information could mislead you into mnaking decisions that could cause problems. For example if the data was collected in 2001 and was data about products that are making a lot of profit then the company may order a lot of that stock which may not provide a lot of profit now.

Complete: If the data isn't complete then mistakes could be made and the right information may not be provided. for example, if a person didn't fill in their address on a order form then they may not recieve the item that they have paid for. 

Relevant: If data is not relevant then time and money could be wasted which would be better spent on collecting data that is relevant to what you are looking for. 

Having the right information is important becuase it can impact a companies decisions. 

The information can be used to:

• Reduce costs
• reduce losses
• help in making good management decisions
• help develop new products,

Good quality information can cost the company so they need to consider a number od factors which can affect the cost of informaiton.

• Collecting data - How is the data collected? Are forms and questionnaires need to be printed? Do people need to be employed to collect the data?
• Inputing the data - How will the data be inputted into the computer system? Is it going to be entered manually or directly (swipe cards etc)? Is any special equipment needed to input the data?
• How often is the data collected - Some data may need to be collected all the time such as in a supermarket checkout, some will need to be collected over a length of time.
• How rigorous are the checks on the data - When the data is inputted it is often checked so if any data is rejected it will need investigating, if there are no checks then errors could occur.
• How long does it take to process the data- Sometimes the data can be processed as soon as it is entered but some companies may chose to process the data at certain times of the day or month.
• How is the information reported- how is the resulting information reported to the users? Is it on a screen or through print outs?

There are errors that can be made in the different stages:

At the data capture stage:

• the form could be filled in wrongly
• a form could be lost before the data is entered.
• A form could be illegible 

At the transcription stage:

• when data is transcribed, human error can cause mistakes.
• a form could be entered twice by mistake

at the transmission stage:

• when data is sent down a transmission medium it can become corrupted

at the processing stage:

• problems with hardware or software might lead to data being corrupted.

GIGO stands for Garbage In Garbage Out which means that if rubbish data gets colelcted then rubbish information will be produced.Validation tries to stop this from happening.

Validation: Is a method used of checking that the data entered is reasonable or sensible. There are different types of validation checks that can be used to check data. Some of which are:

• Presence check - this checks that a data entry has been made.
• Format check (picture check) - checks that data is in the right format (combination of letters and numbers)
• Length check - checks that the correct numbers of characters have been entered.
• Type check - checks that data is in the correct type.
• Range check - checks that data falls within a particular range
• lookup check (list check) - checks that data is in a list of acceptable values
• cross field check - checks that data in two fields corresponds
• check digit - a algorithim used to check artificial numbers

Verification: Is a method of checking by comparison to reduce transcription errors. 

In manual entry systems the data is entered twice and the two entries would be compared.. for example, entering a password twice or entering an email twice.

However if the information  has been entered wrong twice then the information will still be wrong.

ICT systems have many capabilities, some of which are:

• The ability to perform repetitive calculations - the computer systems enable repetitive calculations per second without the standard of the calculations dropping.
• The computerb systems can store a vast amount of data
• the abilitiy to search the system quickly. 
• The ability to communicate - you are able to communicate with people on the other side of the world.
• Fast response times

However there are some limitations to ICT, some of which are:

• Software- it can be unpredicatable, and can be poorly designed. Software can also cost a lot of money.
• Hardware- Hardware can cost a lot of money, and a fast processor is needed to stop people from getting frustrated yet a fast processor can be expensive, hardware can be slow.

Before information gets presented we need to consider:

• The format of the information
• the media you intend to use
• The audience your information is aimed at

Audience - Documents need to be designed appropraite for their audience. You have to think about their:

• Age
• Gender
• Knowledge of the subject
• Individual user needs

The format is the style in which the information is presented and organised. The style includes:

• Text,
• Grpahics - graphs, charts, diagrams, photos etc
• tabular (tables)
• audio
• video
• animations

there are some factors which will affect the choice of format and these are:

• the needs of the user - for example, a blind person would prefer the format to be audio rather than text.
• the complexity of the information - for example figures may be easier to interpret when they are presented as graphs.

Media is the means by which the information is communicated. Such as:

• Paper based (newspapers, books etc)
• Screen based (TV, Websites)
• Audio
• Video
• Multimedia

There are some factors which affect the choice of media and they are:

• The nature and complexity of the information 
• Time needed to study the information 
• the needs of the user
• Lifespan of the information - some information changes every second or minute and some doesn't change for long periods of time.

Exporting means formatting the data so that it can be used by another application (so that two applications can share the same data)

Importing means the ability of one software package being able to read and use data produced by another software package.

Importing and exporting information when presenting information can be very useful as it can allow the same information to be presented using different media.

However, care must be taken when copying or moving information, for example a presentation with movies and sound will not be able to play files unless they are copied with it when it is moved to another computer. 

Compression is the storing of data in a format which requires less space.

Images, audio and video files can be extremely large and take up a lot of space. so compressing files makes their size smaller so they are quicker to load/download.

when a file is compressed:

• It allows more files to be stored on the storage device
• makes the information faster to upload
• makes the information faster to download
• makes it faster to load when viewed by a piece of software
• makes it faster to transfer if it is required as an attachment to an email.

Communiaction between devices is necessary to share information and used shared devices (peripherals).

Communiation requires:

• Appropriate hardware
• suitable software
• compatibility

communication can also be necessary between software applications on the same system; transferring a set of calculations in a spreasheet into a table in a word processor.

For effective communication protocols are needed; a protocol is a set of rules used to ensure the proper transfer of information between computers and between application packages. (IP means internet protocols).

If information is being exchanged between applications then a compatible format can be found. 

A network is a linked set of computer systems of sharing computer power, resources and data. There are different types of networks some of the main ones are:

• LAN (local area network) - is a network where the computer systems are all situated relatively close to each other. Direct physical connection is possible.
• WAN (Wide area network) - is a network where the computers are geogrpahically remote. It makes a range of communication methods including communication satellites.
• VLAN (Virtual local area network) -is a network of computers that behave as if they are connected to the same network cable even though they may not be actually physically locate on different segements of a LAN. 
• The internet

There are some features of a network which are:

• FTP (file transfer protocol)
• news groups
• chat rooms
• online shopping
• online database accessing information

There are two types of LAN: 

• Peer to peer - this is when a small number of computers are linked and can communicate but there is no central file server. It is easy and straightforward to set up and the software to do so is often contained in the operating system.
• Clinet server - This is where there is a main server that controls the network. The computers linked to it are called clients. It requires specialised spftware running on the server and is needed when there is reasonably large number of users.

Hardware:

• each computer needs a network interface card (NIC) and a connection to the network using a cable or wireless)
• a main central computer which stores the shared programs and files
• to connect to a WAN like the internet a modem or gateway/router will be needed.

Software:

• the server needsna network operating system and sfotware to manage and control the network.
• each machine may need a browser to view intranet pages
• eamil software will be needed to communicate across the LAN
• if an internet connection is required then the server will need a connection software to stop unauthorised access from outside the LAN (firewal).

communication protocols:

for computers to communicate over a network they need to follow the same rules for how the data is transmitted and recieved.

Networks can be arranged in different ways and the way that a network is arranged is called a topology of the network.

Bus Networks - are also known as line networks and have one long cable with the file server attached to the middle and the other computers attached along it. Each connection point is called a node and only one signal can travel along the cable at one time so can be slow if there is a lot of traffic.A single break in the cable will stop the network working.

Star networks - In a star network each computer has its own seperate connection to the file server it is faster than a bus network but is more expensive as more cabling is required. If one cable doesn't work it doesn't effect the whole network and extra computers can be added.

Ring Network - in a ring network the computers are linked together by cables in a circle, the data only flows one way round the network and is cheap and fast but can be slow if there is a lot of traffic. It's suitable for a small number of computers and often doesn't have a file server. 

There are pieces of hardware and software that you need in order to connect to the internet, some of these are:

• a computer, but now you can use phones and TVs
• the computer needs to be connected to a telephone line this can be done using a modem or broadband connection.
• A modem (modulator/demodulator) changes the computers digital signals into analogue signals used by the telephone line.
• a broadband connection uses dedicated digital telephone cable so there's no need to alter the computers digital signal.
• a ISP (Internet Service Provider) is needed, ISPs are the companies that create a permanent link to the internet, and provide different packages so that each user can chose the connection that most appropraite to them.
• a browser which is the computer software that allows the user to view internet pages.
• Plug-ins are needed if the user wants to hear sounds or watch movies from internet pages.

An intranet is like a mini-internet which runs over a single organisations netwrok. It uses the same protocols as the internet and has similiar facilities but is kept private and can only be accessed by authorised users.

An extranet is like a intranet but allows people to connect from outside via the internet, users are given a password so that they can access data on the companys internal servers. Extranets need extra security to stop external users from hacking in.

Advantages of having an intranet:

• the intranet can be customised to serve the companies needs most effectively.
• communication and data retrieval is usually faster as everyone is on the same network.
• it cannot be freely accessed by external users so the data stored there is safer.
• Data can be encrypted easily when sent as everyone is on the same network.

Disadvantages of having an intranet:

• It costs a lot more to set up and maintain.
• Only certain users with specialist knowledge and training are able to update it.

Search engines:

If you are wanting to search the internet for something then you can use a search engine such as Google where you type a keyword and you will see a list of websites that use the keywords. 

Most search engines will search for all keywords entered by default and have their own setting you can select from such as showing only english websites, but different search engines work in different ways. 

Features of email:

• Creating a message
• sending and recieving a message
• forward a message
• attachments
• prioritising
• group sending
• Carbon copy (cc) - recipients can see who else got the message
• blind copy (bcc)- recipients don't know another person got the message
• instant acknowledgment

The advantages of emails is that it is fast and cheap and it can be sent to lots of people and attachments can be sent easily.

The disadvantages of emails are that viruses can be sent through attachments, users can get lots of spam,and not everyone has their own email account.

Advantages:

• Hardware can be shared
• software and data can be easily shared and transferred between machines.
• a user can access their files from any computer on the network.
• Files can be managed a lot easier

Disadvantages:

• extra equipment is needed
• if the network breaks down you won't be able to access their data or programs
• users have less control over how the computers are set up
• networks can be very slow
• there's an increased risk of being infected by viruses from other peopl's machines.

There are Laws that have been put in place by the Government to prevent and stop Computer crimes. 

Computer crimes and malpractise include:

• Introducing Viruses
• Hacking and cracking
• Publishing inaccurate, libellous, or offensive material.
• Using the internet to recruit for illegal groups
• Hiding your identity
• Blackmail and stalking
• Bogus websites and credit card fraug
• Money Laundering
• Buying and selling illegal items
• Illegal downloads

Computer Misuse Act - aims to stop the problem of hacking and make sure that hackers are prosecuted. There are 4 offences which break this law which are:

• unauthorised access to computer material
• unauthorised access with intent to commit or facilitate a crime
• unauthorised modification of computer material
• making, supplying, or obtaining anything which can be used in computer misuse offences.

If you commit these offences the legisaltion makes sure that hackers are punished by giving fines and prison sentences:

• Offence 1- Up to 6 months prison and/or hefty fine
• offence 2- up to 5 year prison sentence and/or hefty fine
• Offence 3- Up to 5 year prison sentence and/or hefty fine
• Offence 4- Up to 5 year prison sentence and/or unlimited fine

The Copyright, Designs and Patents Act has two purposes which are:

• to ensure people are rewarded for their endeavours 
• to give protection to the copyright holder if someone tries to sopy or steal their work.

There are a variety of different Copyright offences but some of the ones linked with ICT are:

• Copying software
• copying or downloading music
• copying images or photographs from the web
• copying text from webpages and using it in your work or posting it onto your website and pretending it's your own work. 

The Data Protection Act has eight prinicples which protect service users from having their data and contact information from being seen. These eight principles are:

• Personal data should be obtained and processed fairly and lawfully
• Personal Data can be held only for specified and lawful purposes.
• Personal data should be adequate, relevant and not excessive for required purpose.
• Personal data should be accurate and kept up to date
• Personal Data should not be kept longer than it necessary
• Personal data must be processed in accordance with the rights of the data subject
• appropraite security measures must be taken against unauthorised access
• Personal data cannot be transferred to countries outside the E.U. unless the country has similar legislation to the data protection act.

Symptoms:

• aching, 
• pain in wrists and arms,
•  weakness, 
• swelling, 
• numbness, 
• tenderness, 
• burning sensation.

Causes:

•  typing for long periods of time, 
• using too much force when typing
• chair or workstation is wrong height.

To prevent RSI you need to make sure that the workstation and chair are at the right height, the wrists are supported, and that regular 5 minute breaks are taken at least once every hour. 

DVT is the compression of the veins inside your leg.

Symptoms:

• Swelling in affected leg
• localised heat in the affected leg
• pain in the affected leg

Causes:

• Sitting for long periods of time
• long periods of inactivity

prevention:

• take regular breaks
• stand up and move around
• use adjustable chair
• sit with suitable posture

Symptoms:

• burning, itching eyes
• blurring, hazy or double vision
• headache
• nausea
• fatigue

causes:

• staring at a computer screen for long periods of time,
• working in bad light

prevention:

• use non-flickering monitors,
• use suitable lights
• take breaks
• have regular eye tests

Symptoms:

• Back pain
• can cause neck pain

causes:

• poor or awkward posture

prevention:

• use adjustable chair
• use footrests
• use adjustable monitor
• sit with back straight and head up
• don't slouch
• take regular breaks