SSH, or Secure Shell, is a network protocol used to connect to a web server and execute different tasks via a command line. The protocol is employed by many knowledgeable users, because the information transmitted over it is encrypted, so it can't be intercepted on the way by a 3rd party. SSH access may be employed for a variety of things with regards to the type of Internet hosting account. With a shared hosting account, for example, SSH is one of the ways to import/export a database or to upload a file in case the server allows it. If you have a virtual or a dedicated server, SSH could be used for just about everything - you may install software or restart certain services including the web server or the database server that run on the machine. SSH is used largely with UNIX-like Operating Systems, but there are clients which allow you to use the protocol if your personal computer is working with a different OS as well. The connection is established on TCP port 22 by default and the remote server always listens for incoming connections on that port although a number of service providers change it for security reasons.