This portal talks about desktop environments. Technical words can be used but explained.
In graphical computing, a desktop environment provides a graphical user interface solution to operate a computer. The name is derived from the desktop metaphor used by most of these interfaces.
The three predominant desktop environments for installation in Debian are Gnome, KDE and XFCE.
http://www.debian.org/devel/debian-desktop/ - Debian Desktop Homepage
Desktops and window managers
Some Window managers available under Debian:
GNOME: Simple and effective.
KDE: Complete and very customizable.
Xfce: Light and usable.
FluxBox: Light and configurable.
GNUStep: For those who want to discover a new informatic experience.
Wmii: Try the « tiling » experience.
Resources
Display manager like XDM, GDM, WDM, or KDM
External links
Desktop_environment definition
http://www.enlightenment.org - Enlightenment (E16 and up)