This document summarizes the key differences between comets, asteroids, and meteors. Comets originate from the Kuiper Belt and Oort Cloud, are composed of ice and frozen gases, and have highly elliptical orbits. Asteroids originate from the Main Asteroid Belt between Mars and Jupiter, are composed of silicates and metals, and have more rounded orbits. Meteoroids enter Earth's atmosphere and become meteors as they burn up, with fragments that survive impact becoming meteorites. Studying the composition of comets, asteroids, and meteorites provides clues about the early solar system and impacts that affected Earth.