SSH, which is an abbreviation for Secure Shell, is a network protocol used to exchange encoded info between a client and a server, making it impossible for unauthorized parties to intercept any info. Many tech-savvy customers favor SSH due to the improved security level. The connection is made and the commands are sent through a command line. The offered options depend on the type of Internet hosting service - on a shared server, in particular, files may be relocated or deleted, databases may be imported and exported, and archives may be set up or unpacked. On a virtual or a dedicated server, your choices are a lot more - the web server and the database server can be started/stopped/rebooted, server-side software could be set up and much more. These things aren't possible on a shared server, since full root access is needed and all the other customers on that server would be affected. Even though SSH is used mainly with UNIX-like Operating Systems, there are SSH clients for other OSs as well - Windows, Mac OS, etc.