PATH

To see your current PATH: $ echo $PATH /usr/local/bin:/usr/bin:/bin:/usr/bin/X11:/usr/games

What this means, is if the application you're trying to run is in a directory listed in your PATH, then you don't have to type the complete /path/to/the/application. In this example, I'm trying to run a command called foo in /home/user/bin/

$ foo foo: command not found

$ /home/user/bin/foo Command Initialized, welcome to FOO!

but I don't want to have to type out /home/user/bin/foo every single time. How you set your PATH depends on your shell.

$ echo $SHELL

bash
$ echo $PATH /usr/local/bin:/usr/bin:/bin:/usr/bin/X11:/usr/games

The long way: $ export PATH=/usr/local/bin:/usr/bin:/bin:/usr/bin/X11:/usr/games:/home/user/bin/ $ echo $PATH /usr/local/bin:/usr/bin:/bin:/usr/bin/X11:/usr/games:/home/user/bin/ The easier way: $ export PATH=$PATH:/home/user/bin/ $ echo $PATH /usr/local/bin:/usr/bin:/bin:/usr/bin/X11:/usr/games:/home/user/bin/

csh
$ echo $PATH /sbin:/bin:/usr/sbin: $ set PATH=/sbin:/bin:/usr/sbin:/home/user/bin/ $ echo $PATH /sbin:/bin:/usr/sbin:/home/user/bin/