Graph Search is a way to find people, places, and things your friends recommend. When Facebook can't find relevant search results, it will fill in the rest with Microsoft's Bing.
Rasmussen was a former Googler who joined Facebook in 2010. Google bought his startup and turned it into Google Maps, a big success. But Rasmussen also oversaw one of Google's biggest flops: Google Wave.
Google Wave was a collaboration tool for the Web that was shut down in 2010, a year after its splashy launch.
Even though Wave flopped, Rasmussen's contributions to Google were huge, and it was a big surprise when he left the company for Facebook. At the time, he said Facebook was a "once-in-a-decade type of company."
Facebook has needed a product like Graph Search to rejuvenate the social network for a long time. CEO Mark Zuckerberg called the Rasmussen-led project one of Facebook's three core pillars, along with Timeline profiles and the News Feed personalized homepage.
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