What is pressure coefficient and how is it used in aerodynamics?

Pressure coefficient (Cp = (P - P_inf) / (0.5 * rho * V^2)) is a dimensionless number representing local pressure relative to freestream conditions normalized by dynamic pressure. Cp = 1 at a stagnation point, Cp = 0 where local pressure equals freestream, and Cp < 0 where local velocity exceeds freestream. Cp distributions are used to analyze airfoil performance, calculate lift and pitching moment, and visualize pressure fields in CFD and wind tunnel testing.