Rsync

Rsync is a powerful and efficient albeit eclectic command for synchronizing data between file systems across networks.

It only syncs in one direction at a time, so the name is a bit of a misnomer.

The syntax is like simple copy commands on steroids. It is present natively on linux and MacOS systems.

There is a version of rsync which can be added to the Windows git-bash shell that allows its use on Windows.