Bounce is the angle of the wedge from the sole (bottom of the wedge shape) to the leading edge. Bounce is built into the sole of a wedge to keep it from digging into the turf or sand. This is probably the most neglected part of your equipment needs relative to your playing style and could be a mis-diagnosed problem with your chipping or pitching. Why are there different bounces to wedges you ask?
Two reasons. The first has to do with your style of play. Are you a ‘digger’ or a ‘sweeper’ of the ball when you pitch or chip?
A ‘digger’ is someone who will hit the turf a little harder, that is, with more angle of attack and take more turf.
A digger will need more bounce on the club so that the club’s leading edge to reduce the amount of turf taken. Even in a small chip shot the can be soiled removed when the club is ‘dug in’.
A sweeper as a lower angle of attack and they will need a wedge with lower bounce.
The second reason and probably the most important are the conditions that you play. Do you generally play on a soft or hard course? Is the course that you normally play wet or dry? Wet conditions require a wedge with more bounce so the club does not dig into the turf. In dryer conditions the club needs to dig into the soil or turf a bit more so you will need a wedge with less bounce.
http://www.youtube.com/watch?v=0y3nXraCTtY