The main reason why Google become the most popular search engine is the fact that it was able to provide the most relevant results to the user searches. Google search results are sorted using an algorithm named page rank. It takes in account the number of ingoing and outgoing links to each page. The original paper can be found at http://dbpubs.stanford.edu:8090/pub/1999-66 Can you see an Indian Name "Motwani, Rajeev" as their partner

Amateur PHP implementation of this algorithm can be found at http://www.phpclasses.org/browse/package/3425.html