A rotodynamic pump is a machine that helps move liquids like water from one place to another. It has a special part called an impeller, which looks like a big fan with curved blades. When the pump starts, it spins very fast and the impeller moves the water around. This creates a force called centrifugal force, which pushes the water out of the pump and into pipes or hoses. Think of it like a grill fan blowing air: the blades of the fan pull air in and push it out fast. The same happens with a rotodynamic pump, only with water instead of air. It's helpful for things like water distribution systems and irrigation, where water needs to be moved quickly and efficiently over long distances.