modified: README.md

modified:   docs/desktop-environments/kde.md
renamed:    docs/desktop-environments/xfc4.md -> docs/desktop-environments/xfce4.md
new file:   docs/display-managers/gdm.md
new file:   docs/display-managers/sddm.md
new file:   docs/display-protocols/wayland.md
new file:   docs/display-protocols/x11.md
new file:   docs/window-managers/hyprland.md
new file:   docs/window-managers/kwin.md

README.md

@@ -3,6 +3,7 @@
 - [Distros](#distros)
 - [Graphical Environment](#graphical-environment)
   - [Display Managers](#display-managers)
+    - [cli - utils](#cli---utils)
   - [Graphical Applications](#graphical-applications)
     - [Gnome Files/Nautilus](#gnome-filesnautilus)
 - [Commands and Utilities](#commands-and-utilities)
@@ -40,9 +41,19 @@ Examples:
 
 - [LightDM (lightweight and flexible)](./docs/display-managers/lightdm.md)
 - [GDM (GNOME Display Manager)](./docs/desktop-environments/gnome.md)
-- [SDDM (used by KDE)](./docs/desktop-environments/kde.md)
+- [SDDM](./docs/display-managers/sddm.md) - Used by [KDE](./docs/desktop-environments/kde.md)
 - LXDM (used by LXDE)
 
+#### cli - utils
+
+check which display manager is currently running on your system.
+
+**Debian:**
+
+``` bash
+systemctl status display-manager
+```
+
 ### Graphical Applications
 
 #### Gnome Files/Nautilus