Though it was the Guardians of Tellus who created the day and night along with the seasons, it was Archangel Itherael who first taught mortals how to best measure the passing of time.
Each of the 4 seasons are divided into 4 lunar cycles; Birth of, Rise of, Fall of, Death of. Each of these lunar cycles consist of 15 days.
Most people in Tellus do not bother with a unit of time above that of the seasons apart from denoting age. Historians and chroniclers do denote a full cycle of the seasons as a year and use that to chronicle events.
In the east the scholars base their years on the fall of the Tellision Republic. So this year in the Eastern calendar is 5013 ARF (After Republic’s Fall).
In the West, The Jade Empire’s the years and eras are named for the current clan that rules the Empire, the 6 cycles devoted to the various Succession Wars are not named in this system. Before the Shogun’s death we were in the 52nd year of the Dragon’s 27th Reign.