Final answer:
The Archean era occurred from 3.8 to 2.5 billion years ago and witnessed the formation of stable continents and the appearance of simple cellular life.
Step-by-step explanation:
The Archean era is characterized by being 3.8 to 2.5 Ga (billion years ago). This era falls within the Archean eon and directly follows the Hadean eon. During the Archean era, the Earth's crust had cooled enough to form stable continents. It was also the time when simple cells, such as prokaryotes, first appeared. Repeated reference to various periods such as the Ediacaran period and era divisions like the Mesoproterozoic and Neoproterozoic attest to the complexity of the geological time scale, which is used to organize Earth's deep history.