pwd # print working directory
ls # list files in directory
cd # change directory
~ # home directory
.. # up one directory
– # previous working directory
help # get help
-h # get help
–help # get help
man # manual
cat # output the contents of a file
mkdir # create new directory
open # open a file with the associated program, a directory with Finder, or a URL with the default web browser
ps # list all running processes
kill # terminate existing process
rmd # permanently delete file
rmdir # remove directory