Git branches have been qualified as topic branches, integration branches,
development branches, feature branches, release branches and so on.
Git has a branch that is the master for development, but it is not
the master of any "slave branch": Git does not have slave branches,
and has never had, except for a single testcase that claims otherwise. :)
다음 글도 참고하시면 좋을 듯해요.
https://lore.kernel.org/all/20200619130058.GA5027@danh.dev/t/