Learning the Unix Operating System

Before you can start using UNIX, your system administrator has to set up a UNIX account for you. Think of this account as your office - it's your place in the UNIX environment. Other users may also be at work on the same system. At many sites, there will be a whole network of UNIX computers. So in addition to knowing your account name, you may also need to know the hostname (name) of the computer that has your account.
Each user communicates with the computer from a terminal or a window. To get into the UNIX environment, you first connect to the UNIX computer. (You may have a terminal that's already connected to the computer.) Next, you start a session by logging in to your UNIX account. Logging in does two things: it identifies which user is in a session, and it tells the computer that you're ready to start working. When you've finished working, you log out - and, if necessary, disconnect from the UNIX computer.

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