Search engine optimization different signals. The leading search engines, Google, Bing, and Yahoo, do not disclose the algorithms they use to rank pages. Some SEO practitioners have studied different approaches to search engine optimization, and have shared their personal opinions. Patents related to search engines can provide information to better understand search engines. In 2005, Google began personalizing search results for each user. Depending on their history of previous searches, Google crafted results for logged in users. In 2007, Google announced a campaign against paid links that transfer PageRank. On June 15, 2009, Google disclosed that they had taken measures to mitigate the
Search engine technology Search engine technology A search engine is an information retrieval software program that discovers, crawls, transforms and stores information for retrieval and presentation in response to user queries. A search engine normally consists of four components e.g. search interface, crawler(also known as a spider or bot),indexer, and database. The crawler traverses a document collection, deconstructs document text, and assigns surrogates for storage in the search engine index. Online search engines store images, link data and metadata for the document as well. The concept of hypertext and a memory extension originates from an article that was published in The Atlantic Monthly