Anti-virus
Anti-virus software is designed to protect your computer from certain types of attacks. Some work in conjunction with firewalls to prevent your computer from being used to pass infections on to other machines. Any computer that does not have up-to-date anti-virus and firewall protection can fall prey to viruses, worms, Trojans and other threats.
Anti-virus programs should be updated on a regular basis. Commercial programs should be renewed and licensed at least annually, but the virus definition files used by these programs should be scheduled to update at the very least weekly.
