The document discusses secrets of minimum viable prototyping based on a presentation given at the Big (D)esign Conference 2015. It outlines 13 secrets which are: 1) Make the one thing that matters high fidelity, 2) Pick methods based on outcome, and 3) Working code wins. The secrets advise on choosing the right type of prototype, building only what is needed, applying rigor appropriately, ensuring the vision and design are correct, and designing based on constraints like platform and size.