After you quit dselect, you’ll be presented with the login: prompt.
You can now log in using the personal login and password you
selected; your system is now ready to use. Let’s examine what it
means to log in and how this process works.
To use Debian, you must identify yourself to the system. This is so
it knows who you are, what you have permission to do, and what your
preferences are.
To this end, you have a _username_ or _login_. If you installed
Debian yourself, you should have been asked to give such a name
during installation. If you are logging on to a system administered
by someone else, you’ll have to ask him for an account on the system
and a corresponding username.
You also have a password, so no one else can pretend to be you. If
you don’t have a password, anyone can log on to your computer from
the Internet and do bad things. If you’re worried about security,
you should have a password.
Many people prefer to trust others not to do anything malicious with
their account; hopefully your work environment doesn’t encourage
paranoia. This is a perfectly reasonable attitude; it depends on
your personal priorities and your environment. Obviously a home
system does not need to be as secure as a military installation.
Debian allows you to be as secure or as insecure as you like.
When you start Debian, you’ll see a _prompt:_ a request from the
computer for some information. In this case, the prompt is login:.
You should type your username and, when requested, your password.
The password does not appear on the screen as you type it. Press
Enter after both the username and the password. If you type your
username or password incorrectly, you’ll have to start over.
If you do it correctly, you’ll see a brief message and then a $
prompt. The $ is printed by a special program called the _shell_ and
is thus called a _shell prompt_. This is where you give commands to
the system.
Try entering the command whoami now. There is a _cursor_ to the
right of the shell prompt. Your cursor is a small underscore or
rectangle that indicates where you’re typing; it should move as you
type. Always press Enter when you’re done typing a shell command.
whoami tells your username. You’ll then get a new shell prompt.
For the rest of the book, when we say to enter a command, you should
type it at the shell prompt and press the Enter key.
When you’re done working, you may want to log out of the system. To
exit the shell, enter the exit command. Keep in mind that if you
remain logged in, someone could come along and use your account.
Hopefully you can trust those in your office or home not to do this;
but if you do not trust your environment, you should be certain to
log out when you leave.