There are a few fundamental differences between Polar and Geostationary Satellites, as written below.
Polar Satellites travel in such a way that they always fly over both the poles of the Earth and always make an angle of 90o with respect to its equator. They follow a sun synchronous orbit which means that their position over Earth always remains the same during a particular time of day. The height of a polar orbit is generally around 700-800 km above the Earth's surface. These are normally used for providing telecommunication services.
Geostationary Satellites, as the name suggests, remain stationary from our reference point of Earth. This means that they travel in such a way that they appear moving along with the Earth.The typical height of a geostationary orbit is around 36,000 km, this provides it with a much larger view of the Earth's surface. They are most commonly employed for weather monitoring.