The key thing to understand is that git is free software and GitHub makes it easier to use that software.
www.bloomberg.com/news/articles/2018-06-06/github-is-microsoft-s-7-5-billion-undo-button
OpenAI v Dota 2
OpenAI first ever to defeat world's best players in competitive eSports. Vastly more complex than traditional board games like chess & Go.
— Elon Musk (@elonmusk) August 12, 2017