It's basically an ode to clear, cutter-less, data visualization. Check out this timetable [2] (horizontal lines: stations, vertical lines: hours, diagonal lines: trains), and your mind will be blown. It's compact, it gives you all the information you need, it can be navigated by your grandma (or your granddaughter) and it likely shows more information than most digital or paper-based system you have ever met, in a smaller format.
[1] https://www.edwardtufte.com/book/the-visual-display-of-quant... [2] https://miro.medium.com/v2/resize:fit:1400/format:webp/0*8zW...