Google officially turns 20 today. Back on Sept. 4, 1998, Google was a two-man operation being run out of a garage in Menlo Park, by a pair of recent Stanford University grads who weren't sure they wanted to become entrepreneurs.
Today, it's become Alphabet Inc — one of the most valuable companies on the planet, employing tens of thousands of people, with a market cap of $852 billion.
Here's a look back on 20 defining moments in Google's history.
1998: Larry Page and Sergey Brin start to show investors their novel search engine, Google, which ranks search results based on links back to individual pages, rather than keywords. Their project, initially called BackRub, garners interest from four angel investors in 1998: Sun Microsystems cofounder Andy Bechtolsheim, Amazon.com founder Jeff Bezos, former Amazon executive Ram Shriram and Stanford professor David Cheriton.
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1999: Page and Brin try, unsuccessfully, to sell their fledgling startup to the now-defunct search giant Excite. They reportedly asked for $1 million, but were turned down by Excite's CEO, who thought the company was overvalued. Later in 1999, Google raises $25 million from traditional venture capital firms Sequoia Capital, Kleiner Perkins Caufield & Byers, and others.
2000: Google launches its first April Fool's Day prank, called MentalPlex, asking people to project a mental image of what they want to search for while staring at an animated GIF. MentalPlex would invariably return an error, for example: "Error: Insufficient conviction. Please clap hands 3 times, while chanting 'I believe' and try again."
2001: Google makes its first acquisition in its corporate history, buying Deja, which forms the basis of Google Groups. Google has since gone on to acquire more than 200 other companies.
2002: Google officially enters pop culture vernacular, as with a character of the TV show "Buffy the Vampire Slayer" making a reference to 'Googling' someone. Yahoo offers to buy Google for $3 billion, an offer that Google declines.
2003: Google moves into 1600 Amphitheatre Parkway in Mountain View, leasing buildings from the now-defunct computing giant Silicon Graphics. 1600 Amphitheater Parkway would become the nexus for the Googleplex, which now spans hundreds of thousands of square feet of office space in Mountain View.
2004: Google goes public in August 2004 at $85 per share, raising a little over $1.9 billion. The company split its stock in 2014, and now trades at around $1,214 per share.
2005: The company launches Google Maps and Google Earth, undercutting the paid GPS navigation market.
2006: Google makes its first mega-acquisition, buying YouTube for $1.6 billion. Despite the hefty price tag, YouTube remains one of Google's most profitable acquisitions to date, generating billions of dollars per year in video advertising revenue.
2007: Google makes its second mega-acquisition, buying advertising service DoubleClick for $3.1 billion.
2008: Google begins distributing early versions of the Android operating system to phone manufacturers. T-Mobile's G1 is the first smartphone to run Android.
2009: Google crosses a major milestone, with people making more than 1 billion search queries on the site per day. The site becomes the dominant search engine in the U.S., with 65 percent market share.
2010: Google launches its first branded smartphone, the Nexus One.
2011: Google makes its single largest acquisition to date, spending $12.5 billion to buy Motorola Mobility. Three years later, Google sold Motorola Mobility to Lenovo for $2.9 billion.
2012: Google crosses another major milestone, reporting annual revenue of more than $50 billion. Last year, it reported revenue of nearly $110 billion.
2013: Google launches Chromecast, a dongle that allows people to stream content from their phones or computers to a TV.
2014: Google buys DeepMind, a U.K.-based artificial intelligence company, for $625 million. It also picks up home automation startup Nest for $3.2 billion.
2015: Google restructures itself as Alphabet, a holding company that owns several companies, including Google. Launching Alphabet was designed to give investors a better picture of profits and losses at Google, by separating the company's expensive "moonshot" projects, like Google Fiber, into separate entities.
2016: Google launches its line of smart home speakers, powered by Google Assistant.
2017: European regulators hit Google with a $2.7 billion fine, for promoting its own shopping results over results from competing shopping services.
2018: Internal protests prompt Google to cancel its involvement in Project Maven, a government effort to use artificial intelligence to automatically process military drone footage.
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