Theodorsen Theory, developed by T. Theodorsen in the 1940s, addresses the aerodynamic behavior of oscillating airfoils. It provides a mathematical framework to analyze the lift and drag forces acting on wings that are moving in a periodic manner, such as those found in flapping flight or during turbulence. This theory is particularly important in the field of aerospace engineering and helps in understanding the dynamics of aircraft and other flying objects. By incorporating factors like frequency and amplitude of oscillation, Theodorsen's work aids in predicting how changes in motion affect aerodynamic performance.