Don't see that question very often. KDE stands for "K Desktop Environment", LXDE stands for "Lightweight X11 Desktop Environment", and Xfce originally stood for "XForms Common Environment". Xfce no longer uses the XForms toolkit, so they changed the acronym from XFCE to Xfce. Oh, and gnome stands for "GNU Networking Object Model Environment".
Mint 16 MATEHP2000 Notebook, 4GB DDR3, ATI Radeon 6310