Gene Spafford, a Purdue University professor who is an expert on cyber security, offers numerous tips on how to make home computers more secure, including:

Get a good anti-virus program, install it, run it regularly and keep it up to date.

Get a firewall and turn it on. The best firewalls are those with NAT (Network Address Translation) routing.

Keep up-to-date with vendor patches on programs. Most can be downloaded from vendor's Internet sites.

Perform regular backups of sensitive data. That allows reloading your computer, if necessary. Store backups somewhere safe, but not next to your computer.

Be very cautious what you download from remote sites. In particular, turn your browser setting on to high security levels, don't allow pop-up menus, and don't install downloaded software from remote sites.

Do not store passwords in a file online unless that file is encrypted all the time.

Do not use the same password for every remote site. If you do, weak security at one site or accidental disclosure will result in ALL your access being compromised.

If you have an "always on" connection (DSL, cable modem) keep your system powered off when you aren't using it.