Structuralism is a theory used to explain social phenomena in terms of the underlying structure. This theory is popular especially in linguistic, anthropology, sociology, psychology etc. Everything is in interconnected form. Nothing is isolated. We can identify anything concerning others. Meaning is created within its structure. Without structure, all thing is meaningless, senseless.
There are two fundamental levels of structure. One is visible and another is invisible. We can see a visible level of structure in the physical world. Any activities, behaviour etc that can be observed are considered as visible. We can interact with them physically or in the social world. The invisible level of structure can not be seen. It is the underlying phenomenon of physical activities or behaviour. Or it can be found in the mental phenomenon.
According to structuralists, everything that happens in the physical world can be analyzed through the underlying structure, whether we are aware or not. The structure is not a physical entity. It is the conceptual framework which is based on that human brain works in binary opposition. To recognize bright, there should be dark. Hot is felt with the sensation of cold.
The structure has three properties: i. wholeness, ii. transformation, iii. self-regulation. Wholeness simply means its parts are not a haphazard collection. They are interdependent with each other and function as a unit. Transformation means the structure is dynamic. It is changeable into varieties of forms. Self-regulation means the transformation but within its structure. The transformation never goes beyond the structural system.