A satellite is an object that orbits around another object. Our Earth is a satellite because it orbits the Sun, and our Moon is a satellite because it orbits the Earth. These are known as natural satellites.
Man-made satellites are machines made by humans that are launched into space and orbit the Earth or another body in space. There are thousands of man-made satellites, and many have stopped working since their launch. They still orbit the Earth due to the Earth’s gravity, but they no longer send or receive signals. There are between one and three thousand functioning satellites currently orbiting Earth.
Man-made satellites serve different functions. Some gather information, while others relay cell phone or television signals. Each satellite is built differently and contains different components depending on its purpose.