Differences between KDE & Gnome

[DB]

Hi all,

As a (self-declared) veteran of 8 months using Fedora 9, I'm 
wondering.... what is the "technical" distinction between KDE & Gnome?

 When I first installed F9, Gnome was the default, so I took it, used 
it, & was "acceptably happy" with it.  Then a month or so ago, following 
a response to the thread about HTML editors, I installed Quanta, 
discovered it needed KDE "things" to work properly, so installed KDE & 
have been "acceptably happy" using it ever since (& enormous "Thanks" to 
whoever suggested Quanta - a super-magic app!!!!!).

Now, I'm wondering--do I "need" to have both KDE & Gnome installed?  Are 
there "things" that only work (properly) in one and not in the other? 
(apart from the bouncy doo-dads which I assume are a KDE TM).  If I keep 
both installed, are all the updates done in one automatically available 
to the other?  Are hand-installed programs equally available?

And...... what the heck is the definition of "widget", "plasma" & 
"plasmoid" -- all the doo-dads around my KDE screen appear to do the 
same things as icons & buttons??

Thanks for your comment (** thanks to all the people who set up all the 
toys & keep them working when I break them  !!!!**)

Dave*      *