Type of Computer Virus

Type Of Computer virus

Computer viruses can be categorized in different ways. If we group viruses by their target, we can divide into the following categories:

Program Viruses

Program viruses infect program files that have extensions such as .com, .exe, .dll, .ovl, and

.scr. Program files are attractive targets for computer viruses because they are widely used and have relatively simple formats to which viruses can attach themselves. The virus becomes active when the infected file is executed. Examples of program viruses are Acid Rain, Alien.298, Amoeba.A, Crazy.A, Umbrella.3173, Sunday, and Cascade.

Boot Viruses

Boot viruses infect the boot records of hard disks. Generally,Boot viruses are considered more dangerous than program viruses. Examples of boot viruses are Danish boot, Devil.941, Eek (b), Disk Killer, Michelangelo, and Stoned Virus.

Macro viruses

A macro is set of commands written by the user to be executed later. For example, if you execute a set of commands often in MS Excel or MS Word, you can save that commands as a macro. A macro virus infect data files. For example, MS word and MS Excel files are susceptible to macro virus attacks, as these programs allow the use of macros. Macro virus spread rapidly, as users share infected documents. Examples of such viruses are Melissa, Concept, and Nuclear.