In sociology, structural functionalism is a school of thought which tries to understand the organization of society. To do this, it focuses on the various parts of a society, like the family and education system (which it calls "social institutions"), and tries to understand how these different institutions influence each other and function, more generally. (Hence the name, functionalism). It is also interested in how these institutions impact the individual.
In contrast, conflict theory takes a completely different view of society. As the name suggests, conflict theorists, like Karl Marx, argue that there is a conflict between different social groups because of an unequal distribution of power, wealth, and resources. In Marx's classic understanding, for instance, he suggests that society is divided into the bourgeoisie and the proletariat. The latter are the victims of exploitation because it is the bourgeoisie who own and control the means of production (the factories, workshops, and so on).
In contrast to functionalists, conflict theorists believe that social institutions, like the family, are designed to maintain the power of one social class over another and to propagate this unequal distribution of wealth and resources.
Functionalism, therefore, seeks to understand the organization of society through its social institutions, while conflict theory argues that society is in the midst of a power struggle between different social groups.
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