Git command `merge`
Definition
Join two or more development histories together.
Advanced usage
Merge <branch> in current branch
$ git merge <branch>
Merge <branch> in current branch with ensure that it will remain in logs
$ git merge --no-ff <branch>
Merge <branch> in current branch with ensure that it will remain in logs with a message for the merge commit
$ git merge --no-ff <branch> -m "message"