Viruses : Introduction

A virus is a special kind of computer program which (usually) has these four features :

• The virus can make copies of itself without the user knowing it is doing this.
• The spread of the virus is triggered by a user action such as running a program or opening an email.
• The virus does something annoying or destructive.
• The virus tries to hide itself so the user can not detect and delete it.

A new class of virus called worms have started to spread across the Internet. A worm has all of the properties of a virus but is able to spread without the user doing anything. If your computer is turned on and connected to the Internet it could get a worm without you doing anything.

There is nothing mysterious about a virus. A virus is simply a program that someone has written.

GCSE ICT Companion 04 - (C) P Meakin 2004