SSH is a protocol that goes beyond what its name implies. SSH is a very useful and flexible protocol that permits all kinds of remote authenticated operations.
First, it replaces telnet. With an SSH client (such as PuTTY), a host can open a command line interface on a remote host and execute commands.
Second, it replaces FTP. From the user’s perspectives, everything that can be done with FTP can be done with SSH. WinSCP is an example of a SSH file transfer client.
Third, it allows the “tunnelling” of other protocols. This is a somewhat advanced topic. Essentially, it allows a port on a remote host to tunnel through an SSH connection, and appears as a port local to the host running an SSH client program. All the tunneled traffic is encrypted, which means it can turn any insecure traffic into remote and secure traffic.