These planets are Mercury, Venus, Earth and Mars. The inner planets are also called the rocky planets, because they are made of rocks. The other part of Earth is made up of continents and islands which have different landforms on them. Examples of landforms are mountains, and plains. Because Earth has so much water, plants and animals can live on Earth.
Earth spins very quickly compared to other planets.
It only takes Earth 24 hours to spin around its axis one time. Earth has big oceans and a lot of water vapor in the air. Earth has clouds made of water vapor. Earth has an atmosphere with a lot of oxygen in it for us to breathe. Earth is the only planet in our solar system which has all the conditions that are needed for animals, plants, and humans to live on it.