spyware

n. computer technology that is designed to secretly gather information about a user (e.g. for an Internet advertising company)

Spyware is computer software that is installed surreptitiously on a personal computer to intercept or take partial control over the user's interaction with the computer, without the user's informed consent.While the term spyware suggests software that secretly monitors the user's behavior, the functions of spyware extend well beyond simple monitoring. Spyware programs can collect various types of personal information, but can also interfere with user control of the computer in other ways, such as installing additional software, redirecting Web browser activity, or diverting advertising revenue to a third party. In an attempt to increase the understanding of spyware, a more formal classification of its included software types is captured under the term  privacy-invasive software.
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