Software that gathers information about a user as he or she navigates around the Web, it is intended to track surfing habits in order to build marketing profiles. Spyware is often included in "free downloads" from the Web, where the license agreement (which so many of us accept without reading) may mention that information about your habits will be transmitted back to the company's Web site. Spyware is a major cause for public concern about privacy on the Internet.
Spyware is a type of software that gets onto computers without their users' knowledge. The resource-hungry programs often render machines unusable causing your Internet experience to be very frustrating. It is necessary for you to download and run anti-spyware programs. Past experience has led to using the a combination of programs in conjunction with anti-adware programs and run them at a minimum once a week. Some programs will find certain malware which you delete, and other programs find other adware and malware, which you also delete. (In a test, I personally had it return more than 800 infected files -- this is a huge amount!) Keep running these programs until you get zero infected files and then run these programs at least once a week.
Spyware has forced us to think about the maintenace of our computers in the same way we maintain other things, such as brushing your teeth, cleaning your house, or oiling your car. For example, as a Windowsuser I had to download a Windows Service Pack and run anti-spyware, anti-adware, and an anti-virus program (with a firewall) in order to protect my information. For personal PC users, sometimes multiple programs are needed, and sometimes one suite will do it; businesses hire professionals to maintain their computer systems and keep these malicious programs off of their network.