When you are finally done exploring your graphical environment, or working with your favorite applications, do not forget to tell the system you are leaving, that is remember to log out in a proper manner.
Logging out can be carried out in many ways. You can use the main menu, log-out icons, right-click on pop-up menus. Let's look at the different procedures:
Click on the K menu and select the Logout [your_user_name]... item. A window like the one shown in Figure 5.14 will appear, asking you for confirmation.
You can right-click on the desktop in an “empty” area and a pop-up menu will be displayed.
Just click on Logout [your_user_name]... and the confirmation window will appear.
Whichever method you use, the screen will shade and a little box will pop up with options. If you click on the OK button the default action will be performed: you will quit the current session and, after all of your windows and the desktop itself have closed, you will be brought back to the login screen.
As you might have noticed, however, there are two other options available in the confirmation window: you can choose to shutdown the system and power off the computer (Turn off computer under KDE, Shut down under GNOME), or to reboot your system (Restart computer under KDE, Restart the computer under GNOME). Again, just click on the OK button after you have selected the desired option.
Whatever you choose, this is the correct and safe way to shut down or reboot your system. You should never push your computer's power button because this could lead to serious problems such as file-system corruption or the loss of data.