The term really only makes sense in the context of systems running the X Window System and/or UNIX, systems which have a GUI, but which may not have all the modern features mentioned above. One way to think of a desktop environment is as a set of tools that make UNIX and X act like the GUIs of Microsoft Windows or Apple Macintosh.
Well-known examples include GNOME, KDE, CDE and XFce; however, there are also a number of other desktop environments, including but not limited to EDE, UDE[?], ROX Desktop[?], GEM[?], PerlTop[?], XPde[?] and arm0nia[?].
Some window managers also include elements reminiscient of those found in desktop environments; the most prominent example for this is Enlightenment.
wikipedia.org dumped 2003-03-17 with terodump