E17 stands for
Enlightenment 0.17, which is window manager for
X-windows.
Since 0.17 all code has been rewritten and Enlightenment has got a more
modular approach, making use of parts like
evas,
ecore,
ebits,
ewd,
ewl,
etox and
edb - which all except
ecore, could be considered separate programs, in addition to being components of the
Enlightenment window manager.