11.   In fact, macro viruses are now the most prevalent form of virus in the wild, according to Symantec, which makes the popular Norton AntiVirus software.

12.   Legend has it that the first macro virus, called Concept, was created by a Microsoft programmer to demonstrate the dangers of the new macro features.

13.   Mac owners can get macro viruses that are passed along by infected Microsoft Word documents.

14.   Macro viruses contain malicious commands that destroy data or interfere with how software runs.

15.   Macro viruses infect a computer in a manner similar to the way a retrovirus, such as the herpes virus, infects the human body.

16.   Macro viruses are now the most common infections in the computer world, according to a new report by the National Computer Security Association in Carlisle, Pa.

17.   Macro viruses commonly arrive hidden inside an innocent-looking E-mail that has an attachment.

18.   Macro viruses hide within a Word document and infect your computer when the file is opened.

19.   Macro viruses usually are written in Word Basic, and hide within documents such as Microsoft Word files.

20.   Melissa is a macro virus.