Most of the constellations visible from the northern hemisphere which are "officially" recognized are of ancient Greek derivation. But other civilizations created their own patterns in the sky based on stories and people that were important to them.It is important to recognize the cultural bias introduced in our vision of the sky by the selection of these constellations.

Many peoples also noticed that the planets, the moon, and comets moved through the sky in a different way than the stars. They noticed that, over time, these objects appeared to move with respect to the constellations.

Because of the rotation of the Earth and its orbit around the Sun, it is convenient to divide the constellations into two groups. Some constellations never rise nor set, and they are called circumpolar. All the rest are divided into seasonal constellations. Which constellations will be circumpolar and which seasonal depends on your latitude.