Linux and Unix su command
Become super user or another user.
su [ - ] [ username [ arg ] ]
|-||Pass the environment along unchanged, as if the user actually logged in as the specified user.|
|username||The name of another username that you wish to log in as.|
|arg||Additional arguments that need to be passed through the su command.|
su - hope
Login as the user hope as if the user hope actually logged in (process all login scripts etc...)
Note: After running the su command make sure to run the exit command. Repeatedly calling su to change users without exiting will create a bunch of idle processes in the terminal.