A satellite is a moon, planet or machine that orbits a planet or star. For example, Earth is a satellite because it orbits the sun
A natural satellite was created by nature, like the moon. The Earth's moon is one example of a natural satellite. Artificial satellites are created by humans, like communications satellites. However artificial satellites are built on Earth and are then taken into orbit by rockets or released by a space station.
The uses of artificial satellites are:
Communication - The geostationary satellites are used for communication purposes like long distance telephone calls, telex, radio , T.V broadcasts etc.
Spying.
Weather forecasting.
Collecting information about outer planets and outer space.
