Turning Off and Logging Out

When you've finished using your Mac, you have several options:

• Put the Mac to sleep.

• Leave the Mac on until the screen saver engages and then, later, the Energy Saver system preference settings put the computer to sleep automatically. (See Chapter 27 for details about the Desktop & Screen Saver and Energy Saver system preferences.)

• Log out of your account so people cannot access your Mac without first entering your (or their) login password.

• Shut down the Mac, which logs out of your account and closes the operating system, before switching off the power. This option saves energy and provides greater safety in case of power failure.

• Restart the Mac. This isn't really a way to finish working with your Mac; rather, it's an option typically used to complete the installation of certain system updates or to change startup disks.


If you cut the power to a Mac without first switching it off (either by pulling the plug or by removing the battery from a MacBook), you risk damaging the files on your Mac. Although this damage may not be immediately noticeable, an accumulation of damage could eventually cause problems, such as applications no longer working correctly or files missing data. Always shut down before disconnecting the power source.

Logging out of OS X

You can log out of Mac OS X when you have finished using your computer. This provides an additional level of security over putting the Mac to sleep because it requires people to enter ...

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