These are the planets that most resemble the Earth, although Earth is the only known planet with the ability to sustain life. All four planets are rocky in composition have metal cores and solid surfaces. Due to this fact, they gain their name terrestrial from the Latin word terra, meaning "land" or "earth." All the terrestrial planets orbit the Sun and rotate on their own axes in the same direction, with the exception of Venus which rotates counterclockwise.
The Jovian planets, Jupiter, Saturn, Uranus, and Neptune are the four planets furthest from the Sun. These planets are regarded as jovian due to the “jupiterlike” qualities they possess. In contrast, they all differ greatly from the Terrestrial Planets in regards to size, composition and density. In addition, unlike the rocky, “earthy” Terrestrials, Jupiter, Saturn, Uranus and Neptune are far larger in size and far less dense which is primarily due to their elemental composition. The Jovian Planets are comprised of lighter elements and are gaseous by nature , which is why they are also known as the gas