Bernoulli's principle states that as the speed of a fluid increases, its pressure decreases. This means that in areas where a fluid flows faster, like in a narrow pipe, the pressure is lower compared to wider areas where the fluid moves slower. This principle helps explain how airplanes generate lift, as the air moves faster over the wings, creating lower pressure above them. In everyday life, you can see Bernoulli's principle at work when you drink through a straw. When you suck on the straw, you reduce the pressure inside it, causing the liquid to rise up and flow into your mouth. This simple action demonstrates how pressure and speed are interconnected in fluids.