Web Analytics:
Statistical or machine learning methods applied to web data such as page views, hits, clicks, and conversions (sales), generally with a view to learning what web presentations are most effective in achieving the organizational goal (usually sales). This goal might be to sell products and services on a site, to serve and sell advertising space, to purchase advertising on other sites, or to collect contact information. Key challenges in web analytics are the volume and constant flow of data, and the navigational complexity and sometimes lengthy gaps that precede users' relevant web decisions.