A computer virus is a program or piece of code that is loaded onto your computer without your knowledge and runs against your wishes. Viruses can also replicate themselves. All computer viruses are man-made. A simple virus that can make a copy of itself over and over again is relatively easy to produce. Even such a simple virus is dangerous because it will quickly use all available memory and bring the system to a halt. An even more dangerous type of virus is one capable of transmitting itself across networks and bypassing security systems.
Since 1987, when a virus infected ARPANET, a large network used by the Defense Department and many universities, many antivirus programs have become available. These programs periodically check your computer system for the best-known types of viruses.
Some people distinguish between general viruses and worms. A worm is a special type of virus that can replicate itself and use memory, but cannot attach itself to other programs.
Also see The Difference Between a Virus, Worm and Trojan Horse in the Did You Know? section of Webopedia.
Featured Partners Sponsored
- Increase worker productivity, enhance data security, and enjoy greater energy savings. Find out how. Download the “Ultimate Desktop Simplicity Kit” now.»
- Find out which 10 hardware additions will help you maintain excellent service and outstanding security for you and your customers. »
- Server virtualization is growing in popularity, but the technology for securing it lags. To protect your virtual network.»
- Before you implement a private cloud, find out what you need to know about automated delivery, virtual sprawl, and more. »