SSH, or Secure Shell, is a network protocol which is used to connect to a server and conduct different tasks using a command line. The protocol is employed by many knowledgeable users, due to the fact that the data transmitted over it is encrypted, so it cannot be intercepted on the way by a 3rd party. SSH access can be employed for lots of things depending on the type of web 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 web server allows it. If you have a virtual or a dedicated server, SSH may be used for just about anything - you can install software or restart particular services such as the web server or the database server which run on the machine. SSH is used largely with UNIX-like Platforms, but there are clients that enable you to employ the protocol if your PC is using a different OS as well. The connection is made on TCP port 22 by default and the remote server always listens for incoming connections on that port even though lots of service providers change it for security reasons.