Google was born when two Stanford University Ph.D students, Larry Page and Sergei Brin, had an idea for a Web search engine that would quickly find the most pertinent information in an ocean of data. They registered the domain name Google.com in 1997 and incorporated as Google in 1998.
The first Google prototype was the 1996 BackRub, a search engine that ran on Stanford computers and quickly outgrew its server. It was around long enough, however, to capture Sun Microsystem co-founder Andy Bechtolsheim's attention, and in 1998 he invested $100,000 in the as-yet-unformed Google. Months later, the little startup running out of a garage was chosen as PC Magazine's top search engine of 1998. Only six years later, Google's IPO sale gave it a market capitalization of over $23 billion.
Google's primary innovation was the use of back-links to gauge how relevant a page was, a system named PageRank after founder Larry Page. Earlier search engines used keywords built into the headers and text of Web pages, which were indexed by engines like Alta Vista. Other search engines, such as Yahoo!, allowed page owners and creators to register Web pages for indexing. Google, however, examined links and anchor links from other websites to determine how relevant a page might be for specified keywords. This revolutionary idea transformed Web searching.