Spyware programs are applications that send information via the Internet to the creator of the spyware, or the publisher. Spyware usually consists of core functionality and functionality for information gathering.
The core functionality appeals to users and entices them to install and use the spyware. The End User License Agreement (EULA) informs users of the information-gathering actions, but most users overlook this information. Information that is sent to the publisher is normally used for improved direct marketing purposes.
The type of sent information differs depending on the spyware program. In order for the publisher to properly digest the gathered data, some spyware programs send a unique identifier with the gathered information.
Users often overlook the information-gathering functionaility of spyware, leaving them unaware that the spyware publisher is gathering data from their computers.
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