RHEL Linux uses Wayland protocol to run graphical applications and provide the graphic user interface. It is a client/server architecture-based display protocol. It sets up the foundation for the display manager and the desktop environment.
The display /login manager
A display/login manager controls the presentation of the graphical login screen. The graphical login screen displays a list of all normal user accounts that exist on the system. It does not list superuser accounts.
If you want to log in as any listed user, select the desired user and enter the password. If wish to log in as any unlisted user, click "Not List?" and enter the username and password for the desired user account.
At the top of the screen, it displays the date and time in the middle, and the accessibility, network connectivity, sound level, and battery/power status options at the top right.
Using the accessibility option, you can enable or disable an accessibility feature. To power off or reboot the system and change the system volume, use the arrowhead available on the right of the options.
To check the network connectivity, use the network icon.
The desktop manager
When you enter a username and password on the login screen, the verifies the credentials. If the credentials are correct, it presents a preconfigured graphical desktop manager. There are many desktop managers such as GNOME, KDE, Cinnamon, MATE, and Unity.
The default desktop manager in RHEL Linux is GNOME. It provides an easy and point-and-click GUI for users to run programs and manage the system.
The default screen of GNOME has an Activities icon at the top left. It allows us to search and access programs. When we click it, shows a list of icons on the left side and a Search box in the middle.
We can use the search box to search any installed application, setting, or file.
The application list includes Firefox web browser, file manager, software updates, GNOME help, shell terminal, and a nine dots icon. If we click the nine dots icon, it displays all available programs, including Settings. The Settings application includes system settings such as Wi-Fi, Bluetooth, desktop background, notifications, regional settings, privacy, sound, power, screensaver, network, and many more.
Comparing CLI and GUI
The following table compares CLI (command line interface) and GUI (graphical user interface) and lists the differences between them.
| CLI (command line interface) | GUI (graphical user interface) |
| It is complex. | It is easy to use. |
| It is fast and lightweight. | It is slow and heavy. |
| It is available on all platforms and environments. | It is not available on the platforms that open connections with remote systems for management and file transfer. |
| It is part of the default installation. You don't need to change any settings during the installation process to install it. The default installation process automatically installs it and presents it as the default option to interact with the system. | It is not part of the default installation. To install it, you must select it on the Software Selections screen. If you do this, the installation process installs it and presents it as the default option to interact with the system. |
| It needs minimal hardware resources. | It needs optimal hardware resources. |
