The invention of satellite is the greatest achievement in the human life. Satellites are used for various purposes. Large distance communication is the major advantage of satellites.

A satellite is an object that revolves around the larger object in a path called orbit. In other words, any smaller object that revolves around the larger object is called satellite. The smaller objects revolve around the larger object in the same path, because the gravitational force exerted by the larger object holds the smaller object.
A satellite is an object that revolves around the larger object in a path called orbit

Example:

Moon is revolving around the earth due to the gravitational force of attraction between the earth and moon. Hence, moon is called as the satellite of earth. Similarly, earth is revolving around the sun due to the gravitational force of attraction between the earth and sun. Hence, earth is called as the satellite of sun.
Gravitational force

Gravitational force is the attractive force exists between any two objects. It is one of the four fundamental forces of the universe. For example, if we throw a stone in the upward direction from the earth it falls back towards the earth. This happens because of the earth exerts the gravitational force on the stone. In the similar way, every object in the universe experiences this force.
What causes gravitational force?

Gravitational force is a very mysterious thing in the universe. No one knows what causes gravitational