ABSTRACT
The classic virus is a program that can ‘infect’ other
programs by rewriting their code to include a copy of
itself. (And ‘programs’ here include macros in Word and
other Office documents.)
Worms are programs whose prime purpose is to infect,
rather than actually doing anything. They aim to copy
themselves from system to system, typically by email,
and it is their very presence which causes damage. A
successful worm can so overload the email system that
whole networks have to be shut down until every in-
fected machine has been cleaned.
