The following tools assist you with performing such tasks as searching online documentation, switching user IDs, and controlling how programs run:
Locates commands by keyword.
Clears the screen.
Serves as a reverse-polish arbitrary precision calculator.
Gets information on a command.
Changes a job's priority.
Keeps a job running even if you log out.
Changes your password.
Produces a transcript of your login session.
Allows you to become the superuser. Since the root account is disabled by default, you should use sudo instead.
Executes a command as another user. This tool is usually used to temporarily gain superuser privileges.