By 2004, search engines had integrated a wide variety of undisclosed factors within their ranking algorithms to lessen the influence of link exploitation. In June 2007, New York Times’ Saul Hansell stated websites using more than 200 different signs are ranked by Google. The leading search engines, Yahoo, Yahoo, and Yahoo, don’t divulge the algorithms they use to rank pages. Some SEO practitioners have examined different approaches to search engine optimization, and have contributed their opinions that were individual. Patents related to search engines provides information to better understand search engines.

In 2005, Google started personalizing search results for every consumer. Determined by their background of previous queries, outcomes were crafted by Yahoo for logged in customers. In 2008, Bruce Clay said that “rank is dead” because of customized research. He opined it might become pointless to talk about how a web site rated, because its position would possibly be different for each user and each lookup.

In 2007, Google announced a campaign against paid links that move PageRank. On June 15, 2009, Google revealed that they had taken actions to abate the effects of PageRank building by use of the nofollow attribute on hyperlinks. Matt Cutts, a well-known computer software engineer at Google, declared as a way to prevent SEO service providers from utilizing nofollow for Page Rank sculpting that Googlebot might no longer handle nofollowed links in precisely the same manner. As an outcome of this change the usage of nofollow prospects to evaporation of page-rank. As a way to prevent the preceding, a search engine expert produced alternative techniques so let Page Rank sculpting and that substitute nofollowed tags with Javascript that was obfuscated. Additionally several alternatives happen to be suggested that include the use of Javascript, Display and I frames.

In Dec 2009, Google announced it would use the websearch background of all its customers to be able to fill search outcomes.

On June 8, 2010 a new web indexing method called Google Caffeine was pronounced. Designed to allow users to find additional articles, forum articles and news outcomes after publication than before considerably sooner caffein was a change to the way Google upgraded its catalog so that you can make things present up quicker on Google than before. Based on Carrie Grimes, the software engineer who pronounced Caffeine for Google, “Caffeine provides 50 per cent more refreshing results for web queries than our last list…”

Yahoo Instant, realtime-lookup, was introduced in late 2010 in an effort to make search outcomes pertinent and more timely. Historically website administrators have invested months or even years optimizing a website to increase research rankings. With the increase in popularity of sociable media websites and websites the motors that were top made adjustments to their algorithms to allow fresh message to rank promptly within the research outcomes.

In February 2011, the Panda update, which penalizes sites including content copied from sources and other websites was announced by Yahoo. Historically web sites have duplicated articles in one still another and gained in search engine positions by engaging in this training, nevertheless Google implemented a brand new method which punishes web sites whose content is not unique. The 2012 Yahoo Penguin attempted to punish websites which utilized tricky practices to improve their positions on the lookup engine, as well as the 2013 Yahoo Humming-Bird update featured an algorithm change developed to improve the natural language running and semantic understanding of web pages of Google.