It is simply a virus that redirects your Google searches to other random sites. This can also happen while you are searching on Yahoo.com or Bing.com. Some sites that you get redirected to are normal everyday websites. Others can be totally unrelated to what you are searching for. Others are potentially dangerous and will attempt to spam, con, or provoke you into (unknowingly) installing a virus. In addition, the redirect virus might randomly create a spam site while you are surfing the web. (eg. VideoCop)