git

git merge-base feature brave-idea : common ancestor of 2 branches

git merge-base --octopus feature brave-idea master : common ancestor
of more than 2 branches

diff of branches : git log --oneline master..brave-idea

revisions included in a, b, or c and excluded from d, e, and f

git log a b c --not d --not e --not f

git log a b c ^d ^e ^f