overmars writes "After years of closely guarding the formula for its search algorithms, Google is opening up a little. The search engine company has kept its search formula a closely guarded secret for two reasons: competition and to prevent abuse, said Udi Manber, Google's vice president of engineering, search quality, in a post on the corporate blog. Manber said the blog post is the first part of a renewed effort at the company 'to open up a bit more than we have in the past.' Manber said the most famous part of Google's ranking algorithm is PageRank, an algorithm developed by Google cofounders Larry Page and Sergey Brin. While PageRank is still in use, it is a 'part of a much larger system,' he said. 'Other parts include language models (the ability to handle phrases, synonyms, diacritics, spelling mistakes, and so on), query models (it's not just the language, it's how people use it today), time models (some queries are best answered with a 30-minutes old page, and some are better answered with a page that stood the test of time), and personalized models (not all people want the same thing),' he said."