Theories of society

What is social stratification? What do class, caste, race, and gender have to do with stratification? Is stratification necessary? What would neo-functionalists and neo-Marxists have to say about it? Where does the US fit into the situation? What is the Veblenian paradox and what does it have to do with stratification from a more symbolic-interactionist perspective? And what role, if any, would contemporary theorists say media and consumption have in stratification.