The text discusses design principles for creating effective maps on the web, highlighting the importance of aesthetics and storytelling in cartography. Two maps are presented as examples, one of Washington Park in Denver, Colorado, and another that showcases every county in the United States, demonstrating how colors, labels, boundaries, and symbols can be used to convey information and create a powerful map. The text also explores additional design principles, such as adding variables to tell a story, incorporating shapes to de-clutter the map, and using features to emphasize unexpected data, which are illustrated through another example of a bivariate map.