Planets- A large celestial body that revolves around the sun in a fixed orbit.
For instance, the earth is a planet.
Jovian planets: Jupiter, Saturn, Uranus, and Neptune are called Jovian planets because they all are similar to Jupiter which is referred to as Jove, an ancient Roman god of sky and thunder.
Jovian planets are also called gas giants as they do not have a solid surface like earth.
Jovian planets are composed of gases like hydrogen and helium with some amount of other gases like methane, ammonia, and water vapours.