A computer virus is a malicious program that can be created by individuals who want to cause harm or disruption to computers and systems. They are coded bits that attach themselves to other programs or applications and, when activated, spread like wildfire. Typically, viruses can be found in a document or program that is downloaded from the internet or distributed via email. The majority of countries consider it illegal to create and spread viruses on computers.
There are many different types of computer viruses that attack computers in a variety of ways. Some depend on a host program to begin their work and others are self-contained and can infect multiple systems without the need for hosting. A computer virus that makes use of a host program to attack computers is often considered to be a worm however, those that do not utilize the method of infection through other programs are deemed to be viruses.
Certain viruses can infect a system immediately upon insertion, while others are inactive and only activate after the user executes the code. The first computer virus, created in 1974, and akin to a biological virus, multiplied quickly and caused damage to the system. One example of an extremely destructive virus is the Stuxnet virus specially designed to destroy computerized centrifuges utilized to enrich the uranium.
The process of making viruses can be complex and not for the faint of heart. However, it can be a great and fascinating way to test your knowledge of computer programming languages and systems. There are numerous resources that can show you how to create a virus if are willing and willing to put in the effort.