window system

Summary

In computing, a windowing system (or window system) is software that manages separately different parts of display screens.[1] It is a type of graphical user interface (GUI) which implements the WIMP (windows, icons, menus, pointer) paradigm for a user interface.

Protocol to interact with Display ServerWindow Manager

Window System is the protocol that the Display Server talks, Window Manager talk using the Window System protocol o arrange and style the windows on the screen. ref