A civilization (or civilisation) is a complex society that is characterized by urban development, social stratification, a form of government, and symbolic systems of communication (such as writing). Civilizations are intimately associated with and often further defined by other socio-politico-economic characteristics, such as centralization, the domestication of both humans and other organisms, specialization of labour, culturally-ingrained ideologies of progress and supremacism, monumental architecture, taxation, societal dependence upon farming and expansionism.