Need a dictonary

I am not sure what some of the values are in BeerSmith. I hit the help buttons and the help files are so generic that they really don't help. My latest question is what is "end of running gravity" on the mash tab? Is that the gravity of the wort before sparging or is it the gravity at the point when I stopped sparging?

This is the gravity of the last little bit of wort being drained into your boil pot.  When fly sparging, you don't want this number to be below 1.010.  I don't fly sparge, but my understanding is you can start getting excess tannins and an astrigency type flavor if you over sparge and go below 1.010.  Some brewers will plan their brews to keep sparging until it gets to 1.010 and then stop at that point.

I batch sparge.  I've never had the last of my runnings down to 1.010.  I think the lowest I've ever had was 1.015.

Since I don't fly sparge, I'm sure that a fly sparger will correct me if I'm incorrect.