[plt-scheme] difference between stateful and stateless servlets, and which to use

Hi all,

to be honest, from the documentation it is not clear to me what the  
difference between stateful and stateless servlets is, and which I  
should use for my purpose. If I had to make a guess, I would perhaps  
assume that with stateful servlets, state is kept in memory between  
requests, whereas with stateless ones it would be always directly  
written somewhere, with the help of "stuffers"  - is this at least a  
littel correct?

I 'd be very grateful for a short explanation of the real meanings,  
and also perhaps a hint which to use. I plan to write a simple web  
application, using snooze for the database handling. Up till now I'd  
imagined triggering the database operations "manually"
(directly writing "save!" commands when necessary), but now I wonder  
if this would be the way to go only with stateful servlets, whereas  
with stateless ones I would pack this into a stuffer?

Thanks a lot in advance for any help,
Sigrid