Security is a major concern on the internet. Even Microsoft Corporation and large banks have been vulnerable to hackers who gain unauthorized access to their websites. While your computer may not be the direct target of invatiosn, it is still vulnerble to spyware, viruses, worms and other automated programs that can harvest information from your computer, disable your system and even steal your identity.

Here's a summary of what you need to stay safe on the Internet:

• Firewall: A firewall blocks other computers from having unauthorized access to yours. This is especially important if you have high-speed connection, which is always connected to the Internet. Windows XP has a built-in firewall, but it blocks only incoming traffic. It does not protect against some malicious virus leaving your machine by piggy-backing on an innocent email. Zone Alarm is a free firewall that blocks traffic both ways.
  
• Antivirus: The staples of the antivirus software are Norton and McAfee. These require annual licensing fees. Norton and McAfee also offer bundled packages including a firewall and disk utilities. AVG is a free antivirus program and has received generally positive reviews.
  
• Spyware blocker: Spyware is software that tracks your surfing activity and sends information back to a third party. Most spyware is installed unwittingly, when you download programs or files. If you have Zone Alarm installed, no personal information about you will be transmitted. However, the spyware still resides on your computer. It can cause popup ads, change your browser's home page, and can slow down your machine. Two popular spyware blockers are AdAware and Spybot Search and Destroy.
  
• Email safety: Most Internet service providers and web mail services such as Hotmail have spam filters that block junk email. There are also some third-party spam filters, such as Mailwasher.

A comprehensive list of online privacy tools is at the Electronic Privacy Information Center.