Farming. Humans who were blessed with good water sources and good soil were able to spend less time hunting for food and more time inventing things (like plows and ships with sails).
Indus River Valley (modern day India and Pakistan).
Earliest civilizations depended on land rich with fresh water sources and good soil. River valleys (areas where a river has eroded away an area into a valley) are such a source.
Think of the Fertile Crescent, Tigris and Euphrates rivers.
The adopting of ideas from one culture to another.
A type of belief system, or religion, that worships several gods. (Hindusim, Ancient Greece)
A set of beliefs, or religion, that worships only one god.
The first group of people to practice this were the Hebrews. (Judaism)