SSH, or Secure Shell, is a network protocol that is used to connect to a server and carry out different tasks using a command line. The protocol is used by many knowledgeable users, since the info transmitted over it is encrypted, so it may not be intercepted on the way by a 3rd party. SSH access can be used for a number of things depending on the type of website hosting account. With a shared hosting account, for example, SSH is among the ways to import/export a database or to upload a file when the web server permits it. If you have a virtual or a dedicated server, SSH could be used for just about anything - you could install software or restart certain services such as the web server or the database server which run on the machine. SSH is used typically with UNIX-like Operating Systems, but there are clients that enable you to employ the protocol if your personal computer is running a different Operating System too. The connection is established on TCP port 22 by default and the remote hosting server always listens for incoming connections on that port though lots of providers change it for security reasons.