A Virus is any piece of code that is deliberately written to cause damage or annoyance to computer users on a network. Tens of thousands of different “strains” of viruses have been detected over the years. The effects of these viruses range from harmless messages announcing the presence of an “infection” to malicious deletion of crucial system and data files. The first recorded PC virus was the Pakistani Brain virus detected in 1987.
Common categories of viruses include the following:
Related types of malicious programs that are not strictly viruses because they do not reproduce can have similar effects. These include the following:
Many malicious programs combine the properties of viruses with one or more of these programs and are not easy to categorize.
To keep viruses from proliferating on your network, you can take the following measures: