SSH, or Secure Shell, is a network protocol used to connect to a server and conduct different tasks using a command line. The protocol is employed by many skilled users, since the info transmitted over it is encrypted, so it can't be intercepted on the way by a 3rd party. SSH access may be used for lots of things depending on the type of Internet hosting account. With a shared hosting account, in particular, SSH is among the ways to import/export a database or to upload a file if the hosting server permits it. If you have a virtual or a dedicated server, SSH may be used for practically everything - you may 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 Systems, but there are clients that permit you to employ the protocol if your personal computer is using a different Operating System as well. The connection is created on TCP port 22 by default and the remote server always listens for incoming connections on that port even though many service providers change it for security reasons.