What is lift and how is it generated on an aircraft wing?

Lift is the aerodynamic force perpendicular to the freestream velocity that supports an aircraft's weight. It is generated primarily by the pressure difference between the upper and lower surfaces of the wing, where faster airflow over the curved upper surface creates lower pressure according to Bernoulli's principle. The angle of attack and airfoil shape both contribute to creating this pressure differential and circulation around the wing.