This in turn lifts the wing up. These two molecules are happily floating along, when all of a sudden they are separated. This divider causes the boyfriend to climb over a hill, while the girlfriend gets to travel a straight road below. Well if the boyfriend wants to meet up with his true love, he is going to have to run. On the other side of the wing he meets his girlfriend again.
Most people think a stall is when the engine quits, much like a car engine stalling.
This is not so when talking about aircraft. A Stall, in regards to aircraft is referring to the airflow around the wing. A Stall is caused by the separation of airflow from the wing's upper surface. This results in a rapid decrease in lift. For a given airplane, a stall always occurs at the same angle, regardless of airspeed, flight attitude, or weight.