What is spyware?
The most common definition of Spyware is a program that sends information from your computer to another destination on the Internet without your knowledge and without your explicit consent. The information can potentially include just about anything stored on, or accessible by your computer. In reality, most spyware programs limit themselves to sending specific types of demographic information, such as the URLs you visit on the Internet, or IP and email addresses.
Once installed, spyware software can easily send any required information out to the Internet using the system's current connection. Such transactions occur in the background and are difficult to notice or trace, since most firewall hardware and software, including Windows XP's built in firewall, does not interfere with information going out of the protected computer or network.
Differences between Spyware, Adware and Cookies
Adware is not the same as Spyware. Adware is advertising-supported software. It is software that can be downloaded free from the Web, but contains banner advertisements that create revenue for the company. Adware usually, like Spyware, installs a program on your computer that sends marketing information whenever you are online.
Internet cookies are small files that Web sites create and maintain on your computer. Cookies can store basic information such as your name, email address or the date you last visited the site. This information can be used to personalize your experience using the Web site.
Not All Spyware is Harmful
Spyware can also be used by parents or businesses as a PC surveillance tool. It can be used to monitor activity on a computer, ranging from keystroke capture, snapshots, e-mail logging, chat logging, and more. Some Spyware can limit the amount of time spent on the Internet, or limit the types of Web sites visited.
There are links to free spyware detection and removal tools under the "Free Products" heading on the page you just came from.