An X Window manager is software that manages the windows that applications bring up. For example, when you start an application, there will be a window manager running in the background, responsible for the placement and appearance of windows.
There are three main types of window manager: Compositing, stacking and tiling. This article focuses on selecting the best managers that fit these three classes. Compositing window managers allow windows to be created and drawn separately and then put together and displayed in various 2D and 3D environments, whereas stacking window managers allow windows to overlap by drawing background windows first. The last type, tiling window managers, ensure that no window ever covers another.
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