"First, you might be thinking, "why customize my prompt?" Well,
there are many reasons. ... You can display information such as
the machine you are working on, the current directory, how many
users there are in the system, date, time, etc. You can also add
ANSI color to the display making it easier to read for some
people. In this article I'm going to show you how to customize
the prompt for a BASH shell. I picked BASH since it's the
shell that most users use and is the shell that every distribution
picks as its default shell."
"The BASH uses different variables for its prompt. The main
variable, and the one we are going to focus the most on is PS1.
BASH has 4 different prompts PS1-4. PS1 is the normal prompt that
you see each time you run the shell. PS2 is the extension of PS1
since it is displayed each time you continue a command form the
original prompt. PS3 is used when you execute the select command,
and PS4 is displayed when you trace and execution."
"What I mean about globally or locally is that you might just
want to edit the prompt for your regular user but leave all the
rest of the users with the normal prompt. Now this usually deals
with the file called "profile". A copy of the file is usually kept
in /etc which is the global file that means if a user doesn't have
a copy of the file in their home directory that file will be used
each time you execute the shell. Now you can copy that file to your
home directory and saving it as .profile (cp /etc/profile
~/.profile) that will give you all the options than before but it
also gives you the chance to edit it to your likings and it will
only affect your user."