Wares that wear on PCs

Adware is generally lumped in with spyware, and there’s good reason for that. Whereas spyware is secretly downloaded to computers, adware typically gives users the option to accept or refuse it before the download occurs.

In practice, the explanation of what the adware does is buried deep in an End User License Agreement, which users seldom bother to read.

Two other terms arise frequently in spyware discussions. First, a browser helper object (BHO) is a component loaded by Microsoft Internet Explorer on startup. The BHO shares Explorer’s memory context and can perform actions on open windows. A BHO can also detect events, create windows to display additional information on a viewed page, and monitor messages and actions. Many spyware programs are specifically designed to take advantage of a BHO. Typical exploits include replacing banner advertisements with other ads, monitoring user actions and resetting home pages.

A hijacker is a Trojan that may reset an end user’s home page or search settings to point to other sites—frequently pornography sites loaded with advertising. Some hijackers even prevent users from subsequently changing their browser’s home page or from visiting a particular Web site.
Steve Ulfelder

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About the Author

Steve Ulfelder is a freelance technology and automotive writer.