| login | Initiates your session. |
| logout | Stops all your processes. |
| shutdown | Ends system operation. |
| su | Changes the user ID associated with a session. |
| touch | Updates the access and modification times of a file, or creates an empty file. |
| id | Displays the system identifications of a specified user. |
| logname | Displays login name. |
| uname | Displays the name of the current operating system. |
| who | Identifies the users currently logged in. |
| whoami | Displays your login name. |
| passwd | Changes a user's password. |
Chapter 3, Commands and Processes
Chapter 9, File and System Security
Chapter 2, User Environment and System Information
Chapter 10, Customizing the User Environment