Sociology is one of the social sciences with its main focus on systems of sense-making. Founders of sociology as a discipline are Emile Durkheim and Max Weber. Sociology can overlap with other social science disciplines, e.g. ethnology, educational science, it can also be subdivided in subdisciplinary branches with a specific sectorial focus: medical sociology, sociology of education, sociology of science etc. Applied disciplines often have a multidisciplinary foundation, where sociology is only one of the pillars among others. Agencx theory is an essential element of sociology, but it has also been influenced by other disciplines, e.g. Chomskyean linguistics. Having a look at the complex pedigree of Giddens' sociology, including Durkheim and Chomsky, gives a adequate image of the complexity behind your seemingly so simple question.