Malware

A virus is a manmade program or piece of code that causes an unexpected (usually disruptive or destructive) event.

They are designed to spread from one computer to another and to interfere with computer operation.

A virus might corrupt or delete data on your computer, use your e-mail program to spread itself to other computers, or even erase everything on your hard disk.

Viruses are often disguised as email attachments promising games, greeting cards or images with tempting titles such as "nude pictures of me".

They can also spread through downloads on the Internet. They can be hidden in illicit software or other files or programs on p2p networks.

Find out more about Computer Viruses

Trojans and Backdoors provide outsiders access to your PC. They install, launch and run without the consent or knowledge of the user.

Backdoor Trojans provide the author of the Trojan with remote 'administration' of victim machines. Once a Backdoor is installed, an attacker can take full control of your computer.

A Trojan is best described as a piece of software pretending to be something it is not - they often contain Backdoors, and usually arrive as email attachments.

Trojans are not viruses since they do not replicate, but Trojan horse programs can be just as destructive.

A Keylogger is a type of Malware that invisibly records all keyboard activity, whereas Rootkits hide on your PC and manipulate internal system operations.

Once installed they can be instructed to send, receive, execute and delete files, log activity and harvest confidential data on your computer.

Find out more about Trojans

Your personal information and online behavior is of great interest to certain advertising companies.

Adware is a legitimate, non-replicating program designed to display ads to the end user, based on the monitoring of the users browsing habits. In exchange for the right to use a program without paying for it. It can often take up valuable system resources to run even when the program it was installed with is not in use.

Spyware on the other hand does not notify the user that it is being installed. Spyware distributors have no moral scruples about secretively smuggling software into your system, recording information and spying on everything you do.

Adverts that hijack the start page of your browser also belong in the Spyware/Adware category.

Find out more about Spyware

Computer Worms are viruses that reside in the active memory of a computer and duplicate themselves. Usually transmitted as email attachments they may send copies of themselves to other computers or via Internet Relay Chat (IRC).

Newer network worms/bots use exploits (security holes) to infect a PC, and can reproduce at an astonishing speed. Without your knowledge, your PC can be turned into a spam-sending zombie.

Find out more about Worms

Dialers are small insidious programs that change the Internet access number of a computer that is connected to the internet via a modem (dial-up) so it redirects to a much more expensive number. Cost of calls and connections can run into the hundreds because the numbers are usually international phone calls.

If you're using a modem you can protect yourself by asking your telephone service provider to block all outgoing international calls so they can only be made by first putting in a PIN.

Find out more about Dialers

You certainly can!

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