web 2.0

Like Google, Yahoo! started focusing on personalized in earnest around 2007. Any user willing to sign up for an account soon found that the search engine started to learn from his or her search behavior, identifying themes, topics and web site neighborhoods of particular interest. Relevant pages were given a boost in his or her search engine results.At the same time the search engines started to weed out sites and pages he or she did not find interesting (for instance by measuring how much time the person spent on that page).The information gathered from registered users was also used to influence the results for non-registered users.