[_never_k]

Github inherited it from git, which inherited it from bitkeeper, the DVCS that Linux originally used and the one that inspired git. Bitkeeper used a master/slave architecture that git dropped.

https://github.com/bitkeeper-scm/bitkeeper/blob/master/doc/H...

[waheoo]

The dev that set git to using master says otherwise..

https://twitter.com/xpasky/status/1272280760280637441

[bonzini]

Repositories, not branches. It's just hearsay that the name of the master branch is based on bitkeeper.