what is a computer virus?

Answer 1

Read this:
http://askcomputerexpert.ws43.com/security/

Answer 2

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 manmade. 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.

Answer 3

What Is a Computer Virus

Computer viruses are actually small programs that have the ability to replicate themselves and then spread throughout your system in many ways. This is usually done without a user’s knowledge. Such programs may copy themselves to a shared network resources or mail themselves to E-Mail Contacts that are stored in your address book.

After a Virus has infected your system, it will usually trigger itself in some sort of fashion. It can launch annoying pop up windows that repeatedly place messages on your screen. It can deny you access to your data files and even change your system configuration settings. In advanced stages of infection, a virus can cause major damage to your system as it can corrupt your files and render them unreadable. It can even start deleting files as well. A virus doesn’t always have to trigger itself upon infection. It can actually be programmed to launch at a specific time or on a specific date so that there will be no obvious sign of system infection. A virus will usually disguise itself and may even attach itself to another file, so as to trick a user into running it.

Answer 4

Viruses and spywares are programs launched in the net by people to meet their self intrests. Spywares reside in your PC and spyes your actions. Virus is meant for affecting the normal performance of the PC. I can give a few links that offer free virus and spyware removers...! Norton, AVG , Avast are free antivirus software. Ad-aware, Ewido are free spyware removers. You can download free softwares at
http://fixit.in/antivirus.html and http://fixit.in/spywareremover.html

Answer 5

a computer virus is a evil program which infects the useful information and the files of the operating system to malfunction and destroy the whole system.

Answer 6

its a program that runs by itself and makes your computer act different in bad ways. Malware will harm the computers hardware. Spyware, reports what u have doing on your computer (It spies on you) Ad-ware is like those toolbars that may come on your web browser