one of the libraries underpinning the Linux graphics ecosystem is called the GNU is Not Unix Image Manipulation Program Tool Kit. Its primary competitor was created by a company called Trolltech, and it is the primary library of the Kool Desktop Environment, primary competitor to the GNU is Not Unix Network Object Model Environment.
All of these bind to the X window system, which is named that way because it's the successor to the W window system, which was the window system of the V operating system. It is currently being succeeded by a window system named after a town in Massachusetts.