Spyware

software that monitors a computer user's activity without his or her knowledge and reports it to a central location. The purpose of spyware ranges from purportedly benign (enforcing copyrights, displaying targeted advertisements) to very malicious (stealing passwords and credit card numbers).

The most common way to get spyware on your computer is to install it yourself. This happens when you are tricked into installing free software that supposedly does something else, such as improve your computer's performance or enable access to a web site.

Most spyware runs under Microsoft Windows, which formerly allowed web sites to download and install software on your computer automatically (see ActiveX). Current versions ofWindows ask for permission before installing software, but it is very important for the user to be alert and not give this permission inappropriately. Above all, do not click on web site buttons that offer to do anything to your computer, such as check it or "optimize" it.

Software tools for detecting and removing spyware can be found at www.safer-networking.org and www.lavasoftusa.com.