Google finds, explores, stores and sorts all the indexable pages of the Web, to make them findable through search. The process of discovery and exploration is called Crawling. Google uses several robust programs called bots, or robots, to crawl the whole web. The main among them is Googlebot, but there are other major ones, including the Google blog bot. The process of storing the web pages for referencing in search, and sorting them in some appropriate order, is called indexing.