お使いのコンピューターを誰か他の人が使用できるようにするには、ログアウトしてもいいですし、あるいはログインしたままでユーザーの切り替えを行うこともできます。ユーザー切り替えを行った場合は、使用中のアプリケーションはすべて起動したままになり、ログインしなおせば元のままの状態になっています。

To Log Out or Switch User, click the system menu on the right side of the top bar, click your name and then choose the right option.

If you’re leaving your computer for a short time, you should lock your screen to prevent other people from accessing your files or running applications. When you return, raise the lock screen curtain and enter your password to log back in. If you don’t lock your screen, it will lock automatically after a certain amount of time.

To lock your screen, click the system menu on the right side of the top bar and press the lock screen button at the bottom of the menu.

When your screen is locked, other users can log in to their own accounts by clicking Log in as another user on the password screen. You can switch back to your desktop when they are finished.

To save power, suspend your computer when you are not using it. If you use a laptop, GNOME, by default, suspends your computer automatically when you close the lid. This saves your state to your computer’s memory and powers off most of the computer’s functions. A very small amount of power is still used during suspend.

To suspend your computer manually, click the system menu on the right side of the top bar. From there you may either hold down the Alt key and click the power off button, or simply long-click the power off button.

If you want to power off your computer entirely, or do a full restart, click the system menu on the right side of the top bar and press the power off button at the bottom of the menu. A dialog will open offering you the options to either Restart or Power Off.

他のユーザーがログインしていれば、コンピューターの電源を切ったり再起動したりすることはできないでしょう。他のユーザーのセッションを終了させることになってしまうからです。あなたがシステム管理者であれば、電源を落とすのにパスワードを求められることもあります。