Most commonly an add-on tool-bar for a web browser such as the Google tool bar. These add additional features such as popup blocking and similar that may not be available in the browser software.
Many legitimate toolbars such as the Google or Yahoo toolbar provide various convenient search features, however, many toolbars also include adware and spyware functionality used to track searching behavior and modify the search results to point to an alternative search engine.
Threat Level
Low Risk
Action
Use a quality spyware removal program to remove and prevent future infections. See our recommendations to automatically delete threats like these.