What is a Computer Virus?

A Computer virus is a malicious code or program that can create problem in Computer. This problem can be temporary or can be longer lasting. Computer virus can be divided into two main categories temporary virus and residence virus.

Temporary Virus: Life time of this type of virus is equal to the system life time. That means if you shut down or restart your Computer then this type of virus will be killed automatically. This type of virus can copy itself and spread through the network. This type of virus program is hard to detect by the antivirus because a lot of temporary viruses are developing every day by the malicious people every day. By updating antivirus regularly you can be safe your Computer from this type of harmful virus.

Residence Virus: Life time of residence virus is equal to the life time of the storage device. This type of virus can be stored in the secondary memory of Computer and can also be stored in the portable memory devices such as pen drive, memory card, and CD disk etc. It can copy itself from one storage device to another and one memory location to another. It is not hard to detect and kill by the antivirus software because antivirus software uses a newest technology to check memory of various stored Medias and programs. If it can track that the memory is larger than the size of the software or media then it check for the malicious code and remove it from the programs or Medias.

Veith Risak is the name of the inventor of virus code. He has written virus code using assembly language in 1972. He has also described about virus technology is one of his articles named “Self-reproducing automata with minimal information exchange”.