Secure Shel

The Secure Shell (SSH) protocol is a method for securely sending commands to a computer over an unsecured network. SSH uses cryptography to authenticate and encrypt connections between devices. SSH also allows for tunnelling, or port forwarding, which is when data packets are able to cross networks that they would not otherwise be able to cross. SSH is often used for controlling servers remotely, for managing infrastructure, and for transferring files.

An inherent feature of ssh is that the communication between the two computers is encrypted meaning that it is suitable for use on insecure networks.

SSH is often used to "login" and perform operations on remote computers but it may also be used for transferring data.

It is essentially a more secure version of Telnet as it uses encryption.