Inner Planets:
- The inner planets, also known as the terrestrial planets, include Mercury, Venus, Earth, and Mars.
- These planets are located closer to the Sun compared to the outer planets.
- They are smaller in size and have rocky surfaces.
- The inner planets have higher densities and are composed mainly of silicate rocks and metals.
- They have relatively thinner atmospheres compared to the outer planets.
- The inner planets have shorter orbital periods and revolve around the Sun at a faster rate.
- They have fewer moons compared to the outer planets.
- The inner planets have relatively higher average temperatures, especially Venus, due to their proximity to the Sun.
- They have solid, differentiated interiors with distinct layers, including a core, mantle, and crust.

Outer Planets:
- The outer planets, also known as the gas giants, include Jupiter, Saturn, Uranus, and Neptune.
- These planets are located farther away from the Sun compared to the inner planets.
- They are much larger in size and have thick atmospheres composed of hydrogen and helium.
- The outer planets have lower densities and are mostly composed of hydrogen, helium, and other volatile compounds.
- They have longer orbital periods and revolve around the Sun at a slower rate.
- The outer planets have numerous moons and ring systems.
- They have lower average temperatures compared to the inner planets due to their distance from the Sun.
- The outer planets have fluid or slushy interiors with no distinct solid surface.
- Jupiter and Saturn are classified as gas giants, while Uranus and Neptune are classified as ice giants due to their higher proportion of volatile compounds.

Comparison:
- Size: Inner planets are smaller, while outer planets are larger.
- Distance from the Sun: Inner planets are closer, while outer planets are farther away.
- Composition: Inner planets are rocky, while outer planets are gaseous with volatile compounds.
- Atmosphere: Inner planets have thinner atmospheres, while outer planets have thick atmospheres.
- Orbital Period: Inner planets have shorter orbital periods, while outer planets have longer orbital periods.
- Moons: Inner planets have fewer moons, while outer planets have numerous moons.
- Average Temperature: Inner planets have higher average temperatures, while outer planets have lower average temperatures.
- Surface: Inner planets have solid surfaces, while outer planets have fluid or slushy interiors.
- Classification: Inner planets are terrestrial, while outer planets are gas giants or ice giants.