invention of the plow (women descrimination); Wheel inventions: wheel pottery (mass production), and from that wheels transport (a boat on land), cylinder seal (identifying signature), and from that a writing system (memory aids numbers) on clay – proto-cuneiform. for names they use Rebus principle (Barbie = bar+bee). in Sumerian language all words are one syllable (Ti sound = arrow sign = life word). writing is only for business, not literature, and is done by scribes. writing becomes consistent (same picture) and abstract (simplified picture). schools for scribes. centralized government (priests perhaps) but not kings yet. Uruk has colonies for trade, but not an empire. Earliest urban warfare (Hamoukar). short contact with Egypt.