The number one most important thing to do

The most important thing that I can recommend to keep you safe on the Internet is to update, update and update.  It is very important that you keep your computer up-to-date.  Many of the updates for your Operating System (Window or Mac OS X) are security updates.  These updates fix problems that could potentially allow an attacker into your computer.  Without the update you are pretty much wide open.  So, whenever you see that little yellow shield in the system tray (the area next to the clock in the lower right hand corner) on Windows XP, or the Software Update window appear on a mac, you should make sure to install the updates.

Many people claim that the updates have messed up their computer in the past.  My response, it is better to update your computer and have a problem than to get a virus or be attacked in some other way because you didn’t update.  Usually a problem due to an update will be fixed quickly, whereas removing a virus is usually a difficult process.

You don’t need to just update your Operating System.  You also need to make sure that your Anti-viruses, spyware scanners and other software are updated.  Your anti-virus and spyware scanners are useless against new viruses unless you keep them updated.  Other software can have security flaws that make you more vulnerable as well, so it is important to keep all of your software updated.