Enlightenment, also known simply as E, is a window manager for the X Window System which can be used alone or in conjunction with a desktop environment such as GNOME or KDE. Enlightenment is often used as a substitute for a full desktop environment.

The first version of Enlightenment was released by Rasterman (Carsten Haitzler) on 1996-10-30.

Enlightenment has been under development for over a decade; its latest stable release is version 0.16.8.15.

Version 0.17, also referred to as DR17 or E17, has been in development since December 2000. It is a complete rewrite on DR16 and was designed to be a full-fledged desktop shell, based on the new Enlightenment Foundation Libraries (EFL).