A Geostationary Orbit (GEO) is a circular orbit, located directly above the earth's equator at an altitude of roughly 35,786 kilometers, with zero eccentricity and inclination. There is only one geostationary orbit - a belt circling the earth's equator. A satellite in a geostationary orbit seems to be stationary, when seen from the surface of the Earth, as it moves in the direction of Earth’s rotation with the same speed as the rotation of the Earth.

A geostationary orbit must always be geosynchronous i.e., it should have a period equal to the earth's rotational period. We should also know that, all geostationary orbits must be geosynchronous, not all geosynchronous orbits are geostationary. And this is the reason, we often use these terms interchangeably.

Weather monitoring satellites are geostationary satellites as they need to have a constant view of the same area. Telecommunication and television satellites are some of the satellites in the geostationary orbit, as you want them to continuously transmit to the antenna on the Earth’s surface, without changing the direction of the antenna.