Webopedia on Google+Webopedia on TwitterWebopedia on FacebookTech Bytes Blog
Main » TERM » V »

computer virus (virus)

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.







TECH RESOURCES FROM OUR PARTNERS
LATEST ARTICLES
8 Agenda Apps to Help Students Stay Organized

Webopedia's student apps roundup will help you to better organize your class schedule and stay on top of assignments and homework. Read More »

List of Free Shorten URL Services

A URL shortener is a way to make a long Web address shorter. Try this list of free services. Read More »

Top 10 Tech Terms of 2015

The most popular Webopedia definitions of 2015. Read More »

STUDY GUIDES
Java Basics, Part 1

Java is a high-level programming language. This guide describes the basics of Java, providing an overview of syntax, variables, data types and... Read More »

Java Basics, Part 2

This second Study Guide describes the basics of Java, providing an overview of operators, modifiers and control Structures. Read More »

The 7 Layers of the OSI Model

The Open System Interconnection (OSI) model defines a networking framework to implement protocols in seven layers. Use this handy guide to compare... Read More »