Windowing system

Typical elements of a window. The window decoration is either drawn by the window manager or by the client. The drawing of the content is the task of the client.
A windowing system is a computing term. It refers to a way a computer operating system (OS) displays computer programs on a computer screen. It is a type of graphical user interface (GUI) using windows, menus, and a pointer. Microsoft Windows is a popular OS that uses a windowing system.[1] Each window is an independent part of the screen and typically holds a program or dialog box.[2]
Windowing System Media
The basic components of a GUI: The display server implements the windowing system. A simple window manager merely draws the window decorations, but compositing window managers do more.
The X.Org Server communicates with its clients, e.g. Amarok, over the X11 protocol