Minimum fluidization velocity is the lowest velocity at which a fluid can move through a bed of particles, causing the particles to become suspended and behave like a fluid. At this point, the drag force from the fluid equals the gravitational force acting on the particles, allowing them to float freely. This concept is crucial in various engineering applications, such as in chemical reactors and fluidized bed systems. Understanding minimum fluidization velocity helps optimize processes like gas-solid reactions and heat transfer, ensuring efficient operation and improved performance in industrial settings.