Spyware: Any product that employs a user's Internet connection in the background without their knowledge, and gathers/transmits info on the user or their behavior. Many spyware products will collect referrer info (information from your web browser which reveals what URL you linked from), your IP address (a number that is used by computers on the network to identify your computer), system information (such as time of visit, type of browser used, the operating system and platform, and CPU speed.) Spyware products sometimes wrap other commercial products, and are introduced to machines when those commercial products are installed. See also Adware. Examples Most Common