A type of computer virus that is encoded as a macro embedded in a document. Many applications, such as Microsoft Word and Excel, support powerful macro languages. These applications allow you to embed a macro in a document, and have the macro execute each time the document is opened.
According to some estimates, 75% of all viruses today are macro viruses. Once a macro virus gets onto your machine, it can embed itself in all future documents you create with the application. Anti-virus programs can protect your system against most macro viruses, although new ones are always being created that slip by the anti-virus filters.
