What is a Jovian planet?

Jovian planets, also known as gas giants, is a collective term for Jupiter, Saturn, Uranus and Neptune. The term Jovian came from planet Jupiter, which describes the other gas giants in our solar system which are like Jupiter. These planets are surrounded by a number of moons and rings and their rotation is faster than terrestrial planets. Jovian planets have a dense core surrounded by a huge layer of gas which is made up of hydrogen and helium.