The search giant celebrates its birthday on this day each year, although the domain name was registered on 15 September 1997 and Google was incorporated as a private company on 4 September the following year.
Google began as a research project by PhD students Larry Page and Sergey Brin at Stanford University in 1996, who developed a method of analysing the importance of websites by looking at links between them. Today it's one of the biggest technology companies in the world, and processes over 1 billion searches every day.
Hit the doodle and you'll unwrap search results for the word 'Google' -- which fortunately doesn't break the Internet, at least on this occasion. What happens when you hit 'I'm Feeling Lucky', which takes you to the first result of a search? Fortunately you don't get trapped in an infinite loop of googling Google; instead the Big G has modified the button so it now takes you the page showing off previous doodles.
Other recent doodles include a celebration of, vitamin C discoverer and Queen frontman .
Google has also shown off some clever animated doodles, including aand , both created using HTML5.
Microsoft's rival search engine Bing is getting in on the HTML5 action with its own, which will occasionally appear for US users before European users get to see it some time in the future.
What are your favourite -- or least favourite -- memories of hitting your teen years? What advice would you give Google on this big day? Tell us your thoughts in the comments below or on our Facebook page.
Right, we're going round to our friend's house. What do you mean not until we've finished our homework? That's so unfair!