Our earth is one of the nine planets that orbit round the sun on fixed paths. While it orbits or revolves round the sun the earth also rotates on its own axis. It rotates from west to east. That makes the sun appear first in the east. The part the earth that faces the sun receives sunlight and has day. The part that is way from the sun is dark and has night. The rotation the earth, which takes twenty-four hours, cause day and night, while the revolution of the earth, that takes one year, causes seasons.

The earth is covered with several layers of air and gases. This covering is called Atmosphere. Some of the rays of the sun are harmful to us. But these do not reach the earth because the atmosphere acts as a shield against these rays.

The earth also has many layers. The topmost layer is called the Crust. A vast area of the earth is covered with water or oceans. The layer of the earth that lies below the oceans is called Basalt. Where there is no ocean the earth is dry. We divide this dry area or land into continents or islands. The land is mostly made of rocks called Granites.

The earth is not found in one huge piece. Scientists believe that it is divided into large sections or plates. Underneath the earth’s crust is the layer of hot, liquid rocks. It is so hot inside the earth that some of these rocks are pushed upwards. They break through the crust at its weakest points, usually where two plates meet. Then the plates are pushed apart and we can feel the ground shaking under our feet. These sudden, violent movements under the earth earth’s surface are called Earthquakes. Some times, the ground shakes so hard that buildings fall, roads and bridges are smashed and electric power lines break. Earthquakes also occur under the sea, when this happens it causes giant ocean waves which can be as high as 30 meters.