Outlook Answer Book, The: Useful Tips, Tricks, and Hacks for Microsoft Outlook® 2003

Viruses and Macros

15.34. What Is a Computer Virus and What Types of Viruses Exist?

A computer virus is program that infects your computer and spreads either by self-replication or by changing another file and attaching itself to the file. The latter technique of spreading is known as piggybacking; the virus is spread each time the program that the virus is attached to is run or opened. Another way for viruses to spread is through e-mail. These viruses are known as e-mail viruses, and the vast majority of e-mail viruses spread by infecting a computer and then e-mailing themselves to everybody in the address book stored on the infected computer. Almost all viruses are malicious in nature and are intended to cause damage to your computer software, ...