Structural functionalism refers to the distinct structures or institutions that shape a society and each structure has a specific function or role to play in determining the behaviour of the society. For exaample to maintain security for the members of a society, it has military system to defend the members from exteranl threat, and police system to maintain law and oeder of the society. The systems are the structures of the society and the functions of the systems are to provide security and stability for the society.