Master vs origin/master branches

what is the difference between the master branch and origin/master branch ??

With git, suppose that you cloned a remote git repository. By default, that remote repository is the “origin”. On your local copy of the repository, “master” the name (again, by default) of the base branch (the version, basically) you can work on. “origin/master” is the remote version of that – the version of the “master” branch on the remote repository. git makes it possible to compare branch master (the local one) with origin/master (the remote one), and sync one with the other.