XWayland

XWayland is an X11 server implementation built on top of Wayland. It acts as a bridge between legacy X11 applications and modern Wayland display servers, letting older software run seamlessly on Wayland-based desktops without modification.

When you run an X11 app on a Wayland system, XWayland translates the X11 protocol calls into Wayland native calls, allowing the application window to be composited and managed like any native Wayland window. This is transparent to the user and application.

Example: Running xterm or gedit on a GNOME 40+ session (which uses Wayland by default) works because XWayland automatically handles the translation. Without it, many older Linux applications would be completely incompatible with Wayland desktops.