OS X Lion: Log out, sleep, and shut down
You can log out or put the computer to sleep if you plan to return to work soon, or you can shut down your computer completely.
- To log out, choose Apple menu > Log Out.
- To put the computer to sleep, choose Apple menu > Sleep. You can wake the computer by pressing the Space bar or clicking the mouse.
- To shut the computer off completely, choose Apple menu > Shut Down.
To skip the confirmation message, hold down the Command key when you choose Log Out or Shut Down.
For security, you can lock the screen during sleep or use a password-protected screen saver.