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Window Managers Standards

EWMH (Extended Window Manager Hints) is the primary active standard available right now that isn't tied to a specific desktop. A few WMs support GNOME or KDE - and at least KDE tries to support EWMH, while GNOME is built on the much older ICCCM.

http://freedesktop.org/wiki/Specifications - freedesktop.org's discussion of specifications: "These are not really standards."

by giles