Bernoulli's Equation is a fundamental principle in fluid dynamics that describes the relationship between the pressure, velocity, and elevation of a fluid in motion. It states that in a steady, incompressible flow, the total mechanical energy of the fluid remains constant. This means that as the speed of the fluid increases, its pressure decreases, and vice versa. The equation is often expressed as P + \frac12 \rho v^2 + \rho gh = \textconstant , where P is the fluid pressure, \rho is the fluid density, v is the fluid velocity, g is the acceleration due to gravity, and h is the height above a reference point. This relationship helps explain various phenomena, such as how airplanes generate lift and how water flows through pipes.