GCSE ICT revision

Viruses

2006-11-15T06:29:00.000-08:00

" computer Virus" - this is a phrase coined from biology to describe a piece of sodtware that behaves very much like a real virus (only it spreads from computer to computer rather than person to person!)
Viruses can be prevented by: Using anti-virus software to scan your system daily or weekly, not allowing people to load applications on your system, using special filtering software to prevent downloads of computer programs and not opening suspicious emial or attachments.
Viruses can be spread through files which can be sent through e-mails or by other means, you can

health and safety

2006-11-10T01:51:00.000-08:00

There are various health problems associated with the regular use of computers, such as stress, eyestrain and injuries to the wrists, neck and back.
Employers must take steps to protect employees whose work involves the regular use of computers.

Eyestrain is the most common of these injuries as if a person sitting infront of a computer for long periods of time then he/she will be focusing on the computer screen and this can cause strain to the eyes.

Back problems are also very common because of a persons posture whilst sitting at a computer desk, this is probably due to a poor posture or an awkward position while sitting at a computer.Maintaining good posture can help defeat back problems.

A fully adjustable chair should avoid poor posture
Sit with your back straight and head up

Neck problems can be caused from looking at an awkward positioned monitor so you should position the monitor so that your neck doesnt have to bend too far.

Repetitive Strain Injury (RSI) is damage to the fingers, wrists and other parts of the body due to repeated movements over a long period of time. Repetitive finger, hand or arm movements e.g. typing are just some of the causes. To prevent RSI, make sure your posture is correct, raise your chair or use a cushion so that your wrists can be straight when you type, keep your elbows close to your sides and use wrist rests to avoid bending your wrists too much.

Networks

2006-11-10T01:19:00.000-08:00

A network is a system containing any combination of computers, computer terminals, printers, audio or visual display devices, or telephones interconnected by telecommunication equipment or cables: used to transmit or receive information.

There sare many advantages of a network: messages can be sent between users using a network, also software is cheaper for a network than it is for individual licences. periples, like printers and scanners can be shared on a network.

There are also many disadvantages to a network, these are that if a network collapses, no computers work, also security is an issue as viruses can affect all the computers connected to the network. wiring can be expensive to buy and install which is also a disadvantage.

There are two types of networks: lAN and WAN. LAN is a local Area Network. WAN is a Wide Are Network.
LAN computers are fairly close together, generally within a building, where as WAN computers are spread over larger areas, these can be in different buildings, different sites, or even different countries!!!
LAN uses cable to connnect to a network, where as WAN uses global communications such as telephones, satelite or even the internet.

On a network it is important to have different levels of access becuase it stops data being seen by anyone and it stops files being deleted and settings being changed. A network prevents people from seeing personal information because people are given different access levels controlled by their password and user name, so they have different access rights.

The future of the web

2006-11-03T01:30:00.000-08:00

The British developer of the world wide web says he is worried about the way it could be used to spread misinformation and "undemocratic forces".
The web has transformed the way many people work, play and do business.
But Sir Tim Berners-Lee told BBC News he feared that, if the way the internet is used is left to develop unchecked, "bad things" could happen.
He wants to set up a web science research project to study the social implications of the web's development.
If we don't have the ability to understand the web as it's now emerging, we will end up with things that are very bad
Sir Tim Berners-Lee
Q&A: Web Science
The changes experienced to date because of the web are just the start of a more radical transformation of society, he said.
But Sir Tim is concerned about the way it could end up being used.
He told the BBC: "If we don't have the ability to understand the web as it's now emerging, we will end up with things that are very bad.
"Certain undemocratic things could emerge and misinformation will start spreading over the web.
"Studying these forces and the way they're affected by the underlying technology is one of the things that we think is really important," he said.
Social phenomenon
He insisted his new web science research initiative would be more than just computer science.
When you look at university courses, web science isn't there - it seems to fall through the cracks
Sir Tim Berners-Lee
He said he wanted to attract researchers from a range of disciplines to study it as a social as well as technological phenomenon.
Sir Tim added that he hoped it would create a new science for studying the web, which he believes would lead to newer and more exciting systems.
"All kinds of disciplines are going to have to converge. People with all kinds of skills are going to have to work together to build a new web which is going to be even better," he said.
He also said employers were now beginning to complain that there were not enough people who fully understood the web.
"There aren't any courses at the moment and it hasn't really been brought together.
"We're hearing complaints from companies when they need people that really understand the medium from both the technological and social side.
"When you look at university courses, web science isn't there - it seems to fall through the cracks.
"So we'd like to put it on the curriculum so that there are a lot more people who understand this."
Social challenges
The US-based Massachusetts Institute of Technology and the University of Southampton, UK, will launch the long-term research collaboration that will have a direct influence on the future development of the world wide web.
The free-flow of information has only ever benefited society
Karen Inda, Prague
Our readers' panel The Web Science Research Initiative will chart out a research agenda aimed at understanding the scientific, technical and social challenges underlying the growth of the web.
Of particular interest is the growing volume of information on the web that documents more and more aspects of human activity and knowledge.
The project will examine how we access this information and assess its reliability.

welcome

2006-11-03T01:12:00.000-08:00

Welcome to my GCSE blog. I have created this so that i can get into my revision notes from school and home.