What is the difference between a star and a planet?

Stars are hot bodies that give out light of their own, whereas planets shine only by reflecting light. Stars are composed of gas, but planets can be either gaseous or solid.

The earth is a solid planet. Jupiter is a gaseous one. Nine planets orbit the Sun. In order of distance from the Sun, the are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto.