Fluid dynamics is a branch of physics and engineering that studies the behavior of fluids (liquids and gases) in motion. It involves the study of how fluids flow, interact with their surroundings, and the forces that act upon them. Fluid dynamics plays a crucial role in many scientific and engineering fields, including aerospace, meteorology, oceanography, and mechanical engineering. Researchers in this area use mathematical models, experimental techniques, and computational simulations to analyze and predict the behavior of fluids in various situations.