The Dragon Clan is divided into the Golden Dragon Clan and the Black Dragon Clan, which are just the major categories. Strictly speaking, dragons aren't limited to just Golden Dragons and Black Dragons. Beyond these two are the Oceanic Dragon Clan. However, the Oceanic Dragon Clan lives deep in the depths of the ocean, and has very few opportunities to appear, so much so that they are barely mentioned even in human novels.
Within the Golden Dragons, aside from the most iconic and powerful Gold Dragons, there are also Silver Dragons and Green Dragons.
Within the Black Dragons, aside from Black Dragons, there are also Red Dragons, Azure Dragons, and Poison Dragons.
Even in the Oceanic Dragon Clan, there are divisions such as Pale Dragons, Blue Dragons, and Purple Dragons...