This document provides information about computer viruses including what they are, where they come from, and why they exist. It defines a computer virus as a type of software that copies itself into other programs. Viruses can slow computers down or allow monitoring of user activity. The document discusses the history of viruses dating back to the first "Creeper" virus in the 1970s. It also outlines different types of malware like viruses, worms, and Trojan horses while distinguishing between their characteristics. Finally, it provides tips on how viruses are contracted and recommends installing antivirus software and being cautious of emails and external devices to prevent infections.