A Voronoi diagram is a way to divide a space into regions based on the distance to a specific set of points, called sites. Each region contains all the locations that are closer to one site than to any other. This creates a visual representation of how space is allocated among the sites. Voronoi diagrams are used in various fields, including geography, computer graphics, and robotics. They help in optimizing resource distribution, analyzing spatial patterns, and solving problems related to proximity, such as determining the best location for facilities like hospitals or schools.