ilizations are organized around densely populated settlements, divided into more or less rigid hierarchical social classes of division of labour, often with a ruling elite and subordinate urban and rural populations, which engage in intensive agriculture, mining, small-scale manufacture and trade. Civilization concentrates power, extending human control over the rest of nature, including over other human beings. Civilizations are characterized by elaborate agriculture, architecture, infrastructure, technological advancement, currency, taxation, regulation, and specialization of labour. China is one of the oldest civilizations in the world, originating in the 21st century BCE and continuing to the present day. Historically, a civilization has often been understood as a larger and "more advanced" culture, in implied contrast to smaller, supposedly less advanced cultures, even societies within civilizations themselves and within their histories. Generally civilization contrasts with non-centralized tribal societies, including the cultures of nomadic pastoralists, Neolithic societies, or hunter-gatherers. The word civilization relates to the Latin civitas or 'city'. As the National Geographic Society has explained it: "This is why the most basic definition of the word civilization is 'a society made up of cities.'" The earliest emergence of civilizations is generally connected with the final stages of the Neolithic Revolution in West Asia, culminating in the relatively rapid process of urban revolution and state formation, a political development associated with the appearance of a governing eli