path

Your path variable controls where the computer looks when you enter a command name at the command line. If you want to execute a command located in the directory /home/stu1/bin, you either have to type the full path name (such as /home/stu1/bin/dir), or else you include /home/stu1/bin in your path and the shell will look in the directory once you type dir by itself.

set path=( /usr/bin /bin /home/stu1/bin . )