Kenneth Lane „Ken” Thompson (born February 4, 1943), commonly referred to as ken in hacker circles, is an American pioneer of computer science. Having worked at Bell Labs for most of his career, Thompson designed and implemented the original Unix operating system. He also invented the B programming language, the direct predecessor to the C programming language, and was one of the creators and early developers of the Plan 9 operating systems. Since 2006, Thompson has worked at Google, where he co-invented the Go programming language. Other notable contributions included his work on regular expressions and early computer text editors QED and ed, the definition of the UTF-8 encoding, his work on computer chess that included creation of endgame tablebases and the chess machine Belle.