(Pre - History is before writing or recorded history)

The initial discovery of how to grow food, called the Neolithic Revolution when people changed from food gatherers to food producers, was when civilization began. Surplus, or extra food was the chief reason for the growth of civilizations; fewer people needed to farm, some became craftspeople, traders, and so forth, which made the society more complex. They needed cities with governments, division of labor, writing, calendars, advanced technical skills. These are the 5 elements necessary for civilizations to keep going.
Even as civilizations developed, some people continued to live by hunting and gathering, while others lived pastoral, nomadic lives.