A civilization is any complex society characterized by urban development, symbolic communication forms (typically, writing systems), and a perceived separation from and domination over the natural environment by a cultural elite. Civilizations are intimately associated with and often further defined by other socio-politico-economic characteristics, including centralization, the domestication of both humans and other organisms, specialization of labor, culturally ingrained ideologies of progress and supremacism, monumental architecture, taxation, societal dependence upon farming as an agricultural practice, and expansionism.