A theory is a set of ideas that claims to explain how something works. A Sociological theory is, therefore, a set of ideas that claims to explain how society or aspects of society work.
'Social theories' as a field of study is particularly difficult to accurately determine or define. As understood, social theories are the systematic study of human society, including the processes of social change and transformation, involving the formulation of theoretical (and empirical) hypothesis, explanations, justifications and prescriptions. In disciplinary terms 'social theories' are often associated with sociological theories, and the origins of modern social theories have their origins in the sociological tradition. As can be seen from the range of disciplinary approaches surveyed in this essay, social theory includes the 'social-scientific' approach to studying society (in terms of the disciplines one finds in the social- scientific approach to studying society and social phenomenon- sociology and anthropology, politics, international relations, economics, legal studies, women's studies, cultural studies).
However, social theories may also include the disciplinary approaches of history, philosophy and moral theory and cultural geography. Thus 'social theories' act as an umbrella under which are gathered a range of approaches to thinking about society, explaining social phenomena, and offering justifications for advocating or resisting social transformation.
The historical origins of social theories can be found in the Enlightenment, (sometimes called 'modernity'. It denotes the radical series of changes in European thought, and action, which occurred towards the end of the eighteenth century.), though aspects of modern social theories can be found in pre-Enlightenment thinkers and schools of thought (particularly in political philosophy and political economy). And it is in reaction to the enlightenment and the emergence of 'modern society', that a large part of past and contemporary social theories finds its subject.