Overview
Camber is usually designed into an aerofoil to increase the maximum lift coefficient. This minimises the stalling speed of aircraft using the aerofoil. Aircraft with wings based on cambered aerofoils usually have lower stalling speeds than similar aircraft with wings based on symmetric aerofoils.
An aircraft designer may also reduce the camber of the outboard section of the wings to increase the critical angle of attack (stall angle) at the wing tips. When the wing approaches the stall angle this will ensure that the wing root stalls before the tip, giving the aircraft resistance to spinning and maintaining aileron effectiveness close to the stall.
Some recent designs use negative camber. One such design is called the supercritical aerofoil. It is used for near-supersonic flight, and produces a higher lift to drag ratio at near supersonic flight than traditional aerofoils. Supercritical aerofoils employ a flattened upper surface, highly cambered (curved) aft section, and greater leading edge radius as compared to traditional aerofoil shapes. These changes delay the onset of wave drag.
Read more about this topic: Camber (aerodynamics)