Anything, which moves in a gas or liquid, has its movement controlled by its shape. The slender shape of a body, which is intended to move at high speed through the air in termed aerodynamic, offering minimum resistance to the air.
Inspired by birds, man invented aerodynamic motor car in 1899 and, then, gradually came the aeroplanes, aerodynamic in shape, making transportation easy at high speed.
Below Aerodynamics info from Wikipedia (Read More):-
Aerodynamics is a branch of dynamics concerned with studying the motion of air, particularly when it interacts with a moving object. Aerodynamics is a subfield of fluid dynamics and gas dynamics, with much theory shared between them. Aerodynamics is often used synonymously with gas dynamics, with the difference being that gas dynamics applies to all gases. Understanding the motion of air (often called a flow field) around an object enables the calculation of forces and moments acting on the object. Typical properties calculated for a flow field include velocity, pressure, density and temperature as a function of position and time. By defining a control volume around the flow field, equations for the conservation of mass, momentum, and energy can be defined and used to solve for the properties. The use of aerodynamics through mathematical analysis, empirical approximation and wind tunnel experimentation form the scientific basis for heavier-than-air flight.
http://en.wikipedia.org/wiki/Aerodynamics
