InPrivate Filtering is a privacy feature, unique to Internet Explorer 8, which can be configured to block third-party websites from tracking your browsing activity. Sometimes trusted sites may contain dynamic content supplied by other parties, including advertisements. This content may be used by said parties to track your behavior even though you are not technically on their website. This information is normally used for analytical purposes, but some users prefer to keep their activities on the Web private. The InPrivate Filtering feature gives you more control over what activity, if any, that these third-party sites can track.