Gravity = Bad
Fast enough airspeed in ref to an airfoil that produces a higher air pressure under the wing than over the wing is the amazing effect that overcomes the forces of gravity.
A stall is simply the equalization of the speed of air traveling over the wing (is round so air flow is a lower pressure due to velocity) to the slower air under the wing (due to a flat surface and the drag induced by flaps).
Spoilers create a positive pressure over the wing to to decrease lift as flaps do the opposite of increasing pressure under the wing.
The aircraft only pitches up prior to a stall due to aircraft configuration to maintain positive lift, once equalized the CG of properly designed aircraft should pitch the aircraft nose down. Not to mention pilot input to regain a "positive" airspeed resulting in a positive pressure under the wing.
Trans-Mach airspeeds in aircraft not designed for sonic flight will create a stall at high airspeeds as the center of lift (pressure) travels aft of the wing while the horizontal stabilizer still maintains lift.
Hope this was a simple and accurate explanation as I understand it.