Bing (search engine) are entered and a list of related searches (called "Explore pane") based on semantic technology from Powerset, which Microsoft had acquired in 2008. In July 2009, Microsoft and Yahoo! announced a deal in which Bing would power Yahoo! Search. All Yahoo! Search global customers and partners made the transition by early 2012. The deal was altered in 2015, meaning Yahoo! was only required to use Bing for a "majority" of searches. In October 2011, Microsoft stated that they were working on new back-end search infrastructure with the goal of delivering faster and slightly more relevant search results for users. Known
Search engine technology are, in fact, dead links. Since the search results are based on the index, if the index hasn't been updated since a Web page became invalid the search engine treats the page as still an active link even though it no longer is. It will remain that way until the index is updated. So why will the same search on different search engines produce different results? Part of the answer to that question is because not all indices are going to be exactly the same. It depends on what the spiders find or what the humans submitted. But more important,