1. A computer-implemented method for performing a trusted search, the method comprising: assigning a credibility score to a Web site based on whether the Web site meets at least a portion of trust criteria; storing the Web site in an index of trusted Web sites if the credibility score assigned to the Web site is within a predefined range of credibility scores; and displaying the Web site on a machine if the Web site is determined to contain information that is relevant to a search query.