ICT THEORY

RAM - Random Access Memory

Volitile Memory

• the information can change
• No power = loses information

ROM - Read Only Memory

Non-volitile memory

• Power off = keeps infromation
• On a PC it is BIOS (BASIC INPUT OUTPUT SYSTEM)
• Make a PC work/load up OS (OPERATING SYSTEM) when it is turned on

Processor or a Microprocessor

• Brain of the PC. It completes many basic computations which analyse and display information.
• CPU --> PC
• Processor is another word for CPU.
• Microprocessor is in normal household electronics e.g. washing machine, Microwave.

• Software that makes the connection between the software and human input.

E.g. Click on an icon → it goes to the operator system to find a command → it loads the programme using the command → the CPU processes the command → the GPU (graphics card) displays the output of the command.

A password is a word or phrase which when entered correctly allows access to a secure/private system/file.

• A password is not unique
• The username/account however is unique

Ways to make a password safe

• A minimum of 8 characters
• A mixture of uppercase and lowercase
• Don’t tell anyone
• Use letters and numbers
• Don’t write your password down
• Don’t use easy to guess words or phrases

Physical methods

Physical methods of protection are there to stop unauthorised people physically going to the computer and accessing the IT systems.

• Lock the room when not in use
• Bolt computers to the desk
• Keep windows shut - especially if on the ground floor. Use bars.
• CCTV video cameras to monitor rooms where the computers are and also the corridors
• Passes which are checked by the security guards

Software Methods

• A firewall is designed to help protect a computer network from intruders. It does this by controlling what data can and cannot pass through it.
• A backup to make a copy of the data held on the system in case the original data is lost or damaged.
• Encryption is used to scramble a message in such a way that only the people who are meant to read it can do so.
• Anti-virus software that can detect the presence of a virus within a computer file and warn you there is a problem.
• A User ID identifies who you are when trying to log onto a network.
  

Back something up in order to get something back. The frequency of saving needs to be suitable. E.g. coursework every minute. Having a backup in multiple places is better. However you can download backup software you can get that saves things or you anyways.

• USB memory stick

Offsite Backups

Saving the information to a different place (far away). Cost can be expensive. Security of external backup is not safe. Information is worth more than anything else.

• E-book - It’s an electronic book which can be read on a computer or a specifically designed handheld device.
• Online Newspaper - online version of a newspaper
• Podcast -a digital audio file made available on the Internet for downloading to a computer or portable media player, typically available as a series, new instalments of which can be received by subscribers automatically.
• Bulletin Board - Internet site where users can post comments about a particular issue or topic and reply to other users' postings.
• Wiki - a website or database developed collaboratively by a community of users, allowing any user to add and edit content.
• Instant Messaging - an electronic message sent in real time via the Internet and therefore immediately available for display on the recipient's screen.
• BCC -stands for Blind Carbon Copy and it contains addresses of recipients of the message whose addresses are not to be revealed to other recipients of the message.
• CC - stands for Carbon Copy and is a copy of a note sent to an addressee other than the main addressee.

• DTP -stands for Desktop Publishing and it is the creation of documents using page layout skills on a personal computer.
• WP -stands for Word Processor and it is a program or machine for storing, manipulating, and formatting text entered from a keyboard and providing a printout.
• DVD ROM - a DVD used in a computer for displaying data.
• Online Databases - A web based filing system designed to store information. The database can be accessed by Web scripts and are purchased by subscription.
• Social Networking - The use of dedicated websites and applications to interact with other users, or to find people with similar interests to one's own.
• Podcast - A digital audio file made available on the Internet for downloading to a computer or portable media player, typically available as a series, new instalments of which can be received by subscribers automatically.
• Instant Messaging - sends (someone) an instant message.
• Junk Mail - Unsolicited advertising or promotional material received through the post.
• Phishing Email - Phishing is the attempt to acquire sensitive information such as usernames, passwords, and credit card details (and sometimes, indirectly, money), often for malicious reasons, by masquerading as a trustworthy entity in an electronic communication.

Interviews – Looking for specific information suing a script. E.g. name, address, next of kin, emergency contact details. Takes a long time but would get all information. Good in small numbers.

Questionnaires – Application form for a gym.

Observations – Watching someone’s expressions for answers.

A virus is a malicious piece of software.

How do you get one?

Email attachments - pretend to be a normal file - On click runs/activates virus.

What to do?

1) Firewall - Tries to stop the virus getting on the computer.

2) Anti-virus - If on computer, find virus and deletes it.

Auto update needs to be turned on for the firewall and anti-virus.

LAN - Local Area Network = Small geographic area = Home

WAN - Wide Area Network = Large geographic area = School/World

Mail merge is a technique that allows you to create one letter which the person can use as a template for other letters. You can then take data from a database such as names and addresses and merge it into the template of the letter.

Computer systems now hold personal information on millions of people. This needs to be protected as much as possible so that it stays private and is used properly by those who gathered it.

Data must be:

• collected and used fairly and inside the law.
• only held and used for reasons given.
• not kept longer than needed.
• kept safe and secure.
• not transferred out of the EU.
• information must be adequete and relevant.

This is the lowest level of offence and is one that many of us might be guilty of at some stage in our school or working lives.

 If you have ever guessed or used someone else’s' password to log onto their user area this and then looked at their files, even if you don't change, delete or damage anything, you are still guilty of accessing materials without authorisation - and this is illegal.

This offence carries the risk of being sentenced to six months in prison and/or a hefty fine.

The WIMP interface has now become the most popular computer interface with Microsoft Windows, Apple Mac and Linux operating systems all following the idea.

Windows - a rectangular area on the screen where the commonly used applications run

Icons - a picture or symbol which is used to represent a software application or hardware device

Menus - a list of options from which the user can choose what they require

Pointers - a symbol such as an arrow which moves around the screen as you move your mouse. It helps you to select objects.

RSS Feed - RSS (Rich Site Summary) is a format for delivering regularly changing web content. Many news-related sites, weblogs and other online publishers syndicate their content as an RSS Feed to whoever wants it. An ink which gives you up to date information. Generally a subscription.

Master page - A Master Page is a page that contains mark-up and controls that should be shared across multiple pages in your site.

Hotspot - An area of a graphics object, or a section of text, that activates a function when selected.

Counters – It counts how many people have been on the website.

Hyperlinks - A hyperlink is a piece of text, graphic or button on a web page. When the hyperlink is clicked, it will take you to another location on the same web page or to another web page either in the same website or to a page on the Internet.

Marquees – A marquee is a scrolling piece of text on a website.

Advantages

• Everyone in the room can hear the output from the computer.
• They can help create an atmosphere or ambiance to accompany a presentation
• They help blind people to use the computer because text can be converted into sound

Disadvantages

• The output from speakers can disturb others who are trying to work
• High quality external speakers can be expensive

Advantages

• The sound can only be heard by the user (mostly)
• Portability - lightweight and easy to carry around
• Can listen to music on the move
• Although prices vary, many headphones and earphones are inexpensive

Disadvantages

• If music is played too loudly or for long periods of time there is a risk of permanent hearing loss
• Often not aware of surrounding noises such as cars in traffic or people talking
• If the music is too loud or the headphones not fitted correctly then others can hear an annoying sound from them.
• Can be uncomfortable to wear for long periods of time.
• If the device is large e.g. a computer, it is not easy to move about the room while wearing the headphones