Alexa - Version 6.0 A free software service that helps users become pros at surfing the Web. The service helps users determine the relative value of web sites they visit through a variety of stats and facts about each site and then recommends links of where they might want to go next. These links are determined by a unique search technology that learns from all users' web surfing history. Alexa also solves the problem of 404-not found/server unavailable by providing an archived copy of any publicly available website. Alexa also allows users to share opinions about sites through reviews.