What happens to stages after they break away from the rocket?

After stages break away from a rocket, they typically enter a controlled descent or are guided to a designated area for recovery, depending on the mission design. The spent stages may fall back to Earth, burn up in the atmosphere, or land in the ocean. In some cases, like with SpaceX's Falcon 9, the stages are designed to return to a landing site for refurbishment and reuse. Meanwhile, the remaining stages continue to propel the payload into orbit or on its trajectory.