Spyware is a term used for any programs, cookies or registry entries that secretly gather information about your online activity. These programs are used to transmit data to companies interested in using it for advertising, but the Anti-spyware Coalition reports that spyware is becoming increasingly malicious and being deployed in a more stealthy fashion, using methods that are difficult to detect. Many people consider spyware an invasion of privacy.
Spyware distributors often bundle their software with other software, often from shareware applications or downloads on file-sharing services like Kazaa, Limewire or Morpheus, screensaver download sites, widgets and porn sites. They also rely on security holes and scams to spread their unwanted programs.
Many people consider spyware to violate their privacy, and it certainly can be a nuisance. Spyware can install without your consent, open dangerous security holes and reinstall after being uninstalled. In addition to potentially damaging your system, you may get annoying pop up ads, be exposed to objectionable material, experience a slowdown or have conflicts with other programs. Excessive spyware on a computer may lead to frequent crashes or hangs.