A slip is where you present the side of the plane to the relative wind with the rudder. There are two basic reasons you do this, to increase drag and steepen descent at a given speed, or to slow down if you have excess energy; or to align the longitudinal axis with the runway in a crosswind landing. Either way you "cross control" to lateral drift caused by the rudder application with bank in the other direction.
Stall is an aerodynamic condition where the flow separates and no longer will provide the lift required for controlled flight. This occurs when you achieve an attitude that exceeds the critical Angle of Attack as measured against apparent wind (this means it can potentially happen at any attitude and any speed, although if you're fast enough, you should break the wings or tail off before you stall).
Stall is an aerodynamic condition where the flow separates and no longer will provide the lift required for controlled flight. This occurs when you achieve an attitude that exceeds the critical Angle of Attack as measured against apparent wind (this means it can potentially happen at any attitude and any speed, although if you're fast enough, you should break the wings or tail off before you stall).