Going back to basics..

I've been enjoying flying in FS9 for a number of years and in that time I have managed to fly most types of aircraft , not necessarily correctly, but with a bit of practice I can get them up and I can get them down usually in one piece. However I've decided to go back to basics and try to fly more correctly.
I'm using the default C182 and I'm becoming aware of the effect that the throttle has on verticle speed or rate of climb but I'm still a little bit puzzled by the use of the propeller control. I can see the effect it has on RPM and I'm also aware that the aircraft "moves" when the control is used, but what is it for? I assume it's not the same as "feathering" the prob because when used on the ground I can still taxi normally.
Any advice would be appreciated but please keep it simple. The old grey cells arn't as good as they used to be
Zaphod.
ps
I did have a quick look at the learning center and couldn't find any mention. Perhaps I missed something?
I'm using the default C182 and I'm becoming aware of the effect that the throttle has on verticle speed or rate of climb but I'm still a little bit puzzled by the use of the propeller control. I can see the effect it has on RPM and I'm also aware that the aircraft "moves" when the control is used, but what is it for? I assume it's not the same as "feathering" the prob because when used on the ground I can still taxi normally.
Any advice would be appreciated but please keep it simple. The old grey cells arn't as good as they used to be

Zaphod.
ps
I did have a quick look at the learning center and couldn't find any mention. Perhaps I missed something?