Google's first hire after co-founders Sergey Brin and Larry Page is leaving to take on a role at Khan Academy.

Google's first employee, Craig Silverstein, is leaving the company to join online learning organization Khan Academy.

The news appeared earlier this week via EdSurge, a newsletter about education-tech entrepreneurship, AllThingsD was the first to report.

In a statement provided to PCMag, Google said "Craig's been with Google since the early days. He was instrumental in the development of search and made numerous contributions to Google over the years. We wish him all the best at Khan Academy and know that he will do great things to help them promote education around the world."

Silverstein has been with Google since it was founded in 1998. He was the company's first hire, after of course, co-founders Sergey Brin and Larry Page. In fact, Silverstein has been with Google since it was operated by a couple of Ph.D students out of a Stanford dorm room. Over his 13-year tenure at the Internet company, he held a variety of roles, the first of which was to help create Google's search engine. His last project was mentoring Google engineers, AllThingsD said.

"[Leaving Google] was an extremely difficult choice. I am as passionate about Google's mission now as I've ever been, and as proud of the work we're doing to achieve it," Silverstein said in a farewell email obtained by AllThingsD. "While a lot has changed at Google over the years, I think we've done a remarkable job of staying true to our core mission of making the world a better place by making information more accessible and useful. I am looking forward to pursuing that same mission, though in a slightly different way, at Khan."

Silverstein will work as a developer at Khan, which is also located in Mountain View, Calif.

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