Rigid body motion refers to the movement of an object in which the shape and size of the object remain constant. This means that all points within the object maintain their relative positions to each other, regardless of the motion. Common examples of rigid bodies include cars, books, and furniture. In rigid body motion, the object can undergo translation, where it moves from one location to another, or rotation, where it spins around an axis. The principles of rigid body motion are essential in fields like mechanics and engineering, as they help in analyzing the behavior of solid objects under various forces.