Recognition-by-Components is a theory in cognitive psychology that explains how people recognize objects in their environment. It suggests that we identify objects by breaking them down into basic shapes, called geons. These geons are simple three-dimensional forms, such as cylinders, cones, and blocks, which combine to create more complex objects. When we see an object, our brain analyzes its structure by identifying these geons and their arrangement. This process allows us to recognize objects quickly and efficiently, even if they are partially obscured or viewed from different angles. Overall, Recognition-by-Components highlights the importance of shape and structure in visual perception.