A Pitot Tube is a device used to measure fluid flow velocity. It consists of a tube with an open end facing the flow and a side hole that measures static pressure. By comparing the pressure at these two points, the flow velocity can be calculated using Bernoulli's principle. Commonly used in aviation, the Pitot Tube helps determine an aircraft's airspeed. It is also utilized in various engineering applications, such as in wind tunnels and fluid dynamics studies, to assess the behavior of fluids like air and water in different conditions.