Basic Virus Glossary

Adware
Adware is a type of advertising display software whose primary purpose is to deliver advertising content in a manner or context that may be unexpected and unwanted by users.

Malware
Malware is a general term for a range of malicious software including viruses, worms, Trojan horses and spyware.

Spyware
Spyware is a term used to describe a broad set of applications that send information from a computer to a third party without the user's permission or knowledge. Spyware Trojans and spyware worms are Trojans and Win32 worms that also exhibit behaviour attributed to spyware.

Trojan
A seemingly legitimate computer program that has been intentionally designed to disrupt and damage computer activity. Trojans are sometimes used in conjunction with viruses. A backdoor Trojan is a program that allows other computer users to gain access to your computer across the internet.

Virus
A computer program that copies itself. Often viruses will disrupt computer systems or damage the data contained upon them. A virus requires a host program and will not infect a computer until it has been run. Some viruses spread across networks by making copies of themselves or may forward themselves via email. The term 'virus' is often used generically to refer to both viruses and worms.

Worm
A type of virus that does not need a host program. It has the ability to self-replicate and often will use email and the internet to spread.

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