This article is from the Computer Virus for New Users FAQ, by Nick tanstaafl@pobox.com with numerous contributions by others.
You can't get a virus just by reading a plain-text E-mail message or Usenet
post. What you have to watch out for are encoded messages containing
embedded executable code (i.e., JavaScript in an HTML message) or messages
that include an executable file attachment (i.e., an encoded program file or
a Word document containing macros).
In order to activate a virus or Trojan horse program, your computer has to
execute some type of code. This could be a program attached to an E-mail, a
Word document you downloaded from the Internet, or something received on a
floppy disk. There's no special hazard in files attached to Usenet posts or
E-mail messages: they're no more dangerous than any other file.
 
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