When you turn on your computer, you see the operating system load. Once the system has started, the computer will open the GNOME user interface. GNOME runs atop the operating system and provides a Graphical User Interface (GUI) for the user to interact with. The login screen is the first screen a user will see when GNOME starts.
Types of login screen edit
There are two types of login screen, standard and graphical. GNOME allows the users to select a login theme to customize their computer. Different operating systems provide different “preferred” graphical themes.
A graphical login screen includes a “face browser”, which lets the user visually select their user name, while a standard login screen simply provides text boxes to enter a user name and password. There is no OK button on the login screen; instead, you press Enter once you have entered your password. If you entered your password correctly, GNOME will display the main desktop.
Shutting down the computer edit
But suppose you want to shut down your computer instead. There is a way to do this from the login screen.
In the top-right corner of the login screen you will see two icons. We will be focused on the one with the power-button icon. (The person icon, if clicked, reveals a list of accessibility-related features, such as High Contrast or Mouse Keys.) A dropdown will appear. Confusingly, all you will see there is a button labeled “Dark Style” and another power-button icon. To shut down this computer, you must click the second icon to display the restart and power-off (shut down) commands. Clicking Suspend will put the computer to sleep.
GNOME login screen