What is a Worm?

A worm is a type of virus capable of replicating by resending itself, usually as an email attachment or even as part of a network message. Unlike a virus, a worm doesn't always corrupt or destroy files, it sits in the active memory and uses the parts of the operating system that are automatic and nearly always invisible to the user to replicate itself by sending itself to other terminals on the network. Often the first sign that something is wrong on the system is when the worm has replicated enough times to take up the systems resources, causing tasks to run slow or even come to a halt.

As worms spread by finding vulnerabilities in the operating system, it is essential to keep your security patches up to date. As well as using good Antivirus, Antispyware software and a firewall, users should also be very wary when opening emails from unknown sources and never open or run attachments or visit the links often contained within these emails as these are the most frequent methods of tricking a user into setting off the worm's malicious code.