A quadtree is a tree data structure used to partition a two-dimensional space by recursively subdividing it into four quadrants or regions. This method is particularly useful for organizing spatial data, such as images or geographical information, allowing for efficient querying and storage. Each node in a quadtree represents a rectangular area, and as the data density increases, the area can be divided further into smaller quadrants. Quadtrees are commonly used in computer graphics, geographic information systems (GIS), and spatial indexing. They help improve performance in tasks like collision detection in video games or managing large datasets in mapping applications. By breaking down space into manageable sections, quadtrees enable faster access and manipulation of spatial data.