Fluid Mechanics is the branch of physics that studies the behavior of fluids (liquids and gases) at rest and in motion. It encompasses various principles that explain how fluids interact with forces and with each other, making it essential for understanding phenomena in nature and engineering applications. This field is crucial for designing systems like pipelines, aircraft, and hydraulic machinery. By analyzing fluid flow, pressure, and viscosity, engineers can optimize performance and ensure safety in various industries, from aerospace to civil engineering.