Terrestrial planets are rocky planets with solid surfaces. 

They are made mostly of rock and metal.

They have a solid outer crust.

These planets are smaller compared to gas giants.

They have few or no moons.

They don’t have rings around them.

Their atmospheres are thinner than gas giants.

In our solar system, the terrestrial planets are Mercury, Venus, Earth, and Mars.

Terrestrial planets are often closer to the Sun compared to gas giants.