Lift is a force that is generated when a fluid, such as air or water, flows around an object. It is the component of the force that is perpendicular to the oncoming flow direction. In the context of aviation, lift is the force that holds an aircraft in the air and is mostly associated with the wings of fixed-wing aircraft. It acts in an upward direction to counter the force of gravity, but it is defined to act perpendicular to the flow and therefore can act in any direction. Lift is always accompanied by a drag force, which is the component of the force parallel to the flow direction
. The generation of lift is a result of the interaction and contact of a solid body with a fluid, and it is produced by the motion of the fluid past the object. One simple explanation for the production of lift is that the wing deflects air downward, and the reaction pushes the wing up
