Today I learned that there are standards in the patterns of the bumpy parts on pavements ("tactile paving") that help visually impaired people move around. Apparently there are different patterns that have their own meaning, such as when there are steps ahead or near a platform. Check out this video by Tom Scott that focuses on the patterns used in British streets. The standard they use (“Guidance on the use of Tactile Paving Surfaces”) can be found here.