X Window System Core Protocol - Pixmaps and Drawables

Pixmaps and Drawables

A pixmap is a region of memory that can be used for drawing. Unlike windows, pixmaps are not automatically shown on the screen. However, the content of a pixmap (or a part of it) can be transferred to a window and vice versa. This allows for techniques such as double buffering. Most of the graphical operations that can be done on windows can also be done on pixmaps.

Windows and pixmaps are collectively named drawables, and their content data resides on the server. A client can however request the content of a drawable to be transferred from the server to the client or vice versa.