SSH, or Secure Shell, is a very handy utility. SSH is not an absolute requirement for performing tasks in your server room, but it is one of those things that will make your life a lot easier. With SSH, you are able to execute commands on a different Linux machine as though you were sitting right there in front of it. Sure, you could always walk into your server room, grab the keyboard, and start working, but nowadays remote administration is the name of the game. This is especially true if it's your turn to be on call and an issue comes up at the office. Depending on the nature of the issue, SSH may allow you to fix the problem from home (or even on your smart phone) without having to make the trek all the way to your company's server room. That's not all; SSH also allows you to copy files from one machine to another and set up an actual storage mount to a directory on a server, which can be treated, on your workstation, like the directory were a local part of your filesystem...