“Linux’s graphical user interface is improving, but there comes
a time when we all must descend into that scary and obscure world
of the Linux command line. Though communicating with your
computer via keyboard rather than mouse can be a bit intimidating
at first, most people find that picking up just a few simple
commands can go a long way toward making them much more efficient
and happy Linuxniks.”
“When you type a command on the command line, what you’re
actually doing is telling the computer to execute a particular
program. For example, if you type pwd on the command line and hit
“Enter,” what you’re doing is executing the program named pwd.
While this is a very simple program (all it does is print the name
of the directory you’re in), it is still an executable
program.”
“Sometimes you have to feed a command some extra information
before it can properly execute. Each part of this extra information
is referred to as a command-line argument. So, if you see something
like ls -a foo, the command is ls (which lists the contents of a
directory) and the arguments are -a (which tells ls to list all
types of files in the directory) and foo (which is the name of the
directory you want to see listed).”