What is a display server in Linux? What is it for?

A display server is a program that coordinates input and output between its client and the rest of the operating system, as well as between hardware and the operating system. Basically, with the help of a display server, you can use your computer graphically (GUI). Without the server shown, you will be left with a command line interface (TTY).

The display server provides the framework for the graphics environment, so you can interact with applications using the mouse and keyboard.

X11 (also known as X) is an older display server that has been around for years. It is the most commonly used display server in Linux distributions.

X framework

X11 communication protocol uses X.org server to display servers. It receives input events from the device driver and makes them available to one of its clients.

The display server also receives data from its clients, processes it, and synthesizes it, and on Linux, it passes the data to one of the three kernel components -DRM, GEM, or KMS drivers.

The X.Org server is a display server that relies on a second program, the compositing window manager, for compositing. Such as Mutter or KWin. GNOME uses noise.

According to its website, Wayland is “designed as a simpler alternative to X that is easy to develop and maintain.”

Indeed, Wayland is a modern display server and should replace the traditional X display server.

Its adoption is still in progress. Ubuntu tried switching to Wayland as the default display server for version 17.10, but the experiment was met with negative feedback.

Many GUI applications and their frameworks rely on the X server. These apps don’t work properly on Wayland.

This forces Ubuntu to leave X as the default display server. It still offers the option to use Wayland, but it is no longer the default.

Even today, most distributions use X display servers by default.

Wayland framework

The display server that implements the Wayland display server protocol is called the Wayland synthesizer. Like the X11, the Wayland synthesizer is responsible not only for handling inputs and outputs for its customers, but also for synthesizing — which, compared to the X11, is a synthesizer.

Some Wayland synthesizers are Weston, Mutter, KWin or Enlightenment.

Mill display servers come with their own protocols, unlike those used by X11 and Welland for display Mill servers. It was developed by Canonical as part of Unity’s efforts to become the display server of choice for Ubuntu.

As of 2017, it has been replaced by the Wayland display server for desktop Ubuntu, although Mir’s development of an Internet of Things (IoT) application continues.

Wayland is relatively new compared to Xorg, but not very stable yet. In order to communicate with the display server, the program acting as the client must know how to do this.

Wayland is relatively new compared to Xorg, but not very stable yet. In order to communicate with the display server, the program acting as the client must know how to do this.

Source: https://itsfoss.com/display-server/