First of all, in astronomical matters, there are two types of satellite (from the latin satelles). On one side, means the opaque celestial body that shines through the light reflected from the Sun and that revolves around a primary planet.
On the other hand, artificial satellites are vehicles which orbit around the Earth or another celestial body, and carrying equipment to collect and retransmit them. This type of satellites can have a crew or not.
The only natural satellite of the Earth is the Moon, which has a diameter of 3,476 kilometers and is located at 384.400 km. distance from our planet. By extension, the natural satellite of any planet are called moons.
When a planet and its satellite are of similar masses, experts speak of binary system and not a primary object and satellite. This is the case of Pluto and its satellite Charon.
The satellites of the solar system can be classified as satellites shepherds (when they maintain a ring in their place), satellite co-orbital (when they turn on a same orbit), in satellite-asteroid (they are found around asteroids) or satellite Trojans (when a planet and a satellite have other satellites in the Lagrange points).
On artificial satellites, there are instead of saying that they are space shuttles that are sent into space by the means of a launch vehicle. Once their useful life is completed, it is possible that they orbit and space dust.
Finally, at the general level, a satellite is someone or something that depends on another (a nation, for example) and which is subject to its influence.