Fluid Mechanics is the branch of engineering that studies the behavior of fluids (liquids and gases) at rest and in motion. It examines how fluids respond to forces, pressure, and environmental conditions, and how they interact with solid boundaries. Key concepts include fluid properties (density, viscosity, surface tension), fluid statics (pressure distribution in stationary fluids), and fluid dynamics (motion of fluids, flow patterns, and energy transfer). Principles like Bernoulli’s equation, continuity, and momentum conservation form the foundation of analysis. Fluid Mechanics is essential for designing pipelines, pumps, aircraft, hydraulic systems, and numerous industrial applications.