What is a Computer Virus?

What is a Computer Virus?

A computer virus is a man-made program or code that can cause damage to your data and software on a computer. It is able to replicate usually without knowledge and permission of the computer user.

How does it spread?

They are spread unknowingly from one infected computer to another via emails and instant messaging.

Types of Computer Viruses

Trojan horse- These are programs that claim to do one thing but actually do something else (usually damaging activity).

Resident virus- These dwell in the RAM memory and work by overcoming and interrupting all of the operations executed by the system including corrupting of the files and programs that are opened and closed.

Direct action virus- This has a main purpose of replicating and taking action when it is executed. The batch file of this virus is always found in the root directory of the hard disk.

Overwrite virus- These are characterized by the fact that they delete the information that is contained in the files that they infect, and this renders the files as being partially or even totally useless once they have been infected.

Boot virus- These affect the boot sector of a floppy or hard disk.

Macro virus- These infect files that are created using certain applications or certain programs that contain macros.

E-mail virus- These can infect your desktop email system. They proliferate through e-mail messages and usually replicate by automatically e-mailing copies to all entries in your e-mail address book.

Worm- These are programs that are able to replicate on their own over computer networks. It scans a network for computers with same security hole that it can exploit to infect that machine, scan other machines for that security loophole, and continue replicating itself independently.

One should use licensed anti-virus software to protect one’s computer from computer viruses.