What was the basic social and economic unit on feudal times?

"A king was whoever could act like one and be recognized by his fellows as one, and Germanic tribes tended to elect their kings and to bind them to respect the ancient customs of the tribe. Thus the basic political and economic unit was the most local. For much of Northern Europe and England, it was the Manor, made up of 50 to 250 people, a thousand acres or only a few hundred."