Eighty-one ways to make something understood, in one page. Each picture is labelled with the name of its kind and a number, so you can point at the ones you want.
Subject matter: the NTB Image Portal prototypes, checkout, VAT, receipts and how the experiments are kept apart. Rules quoted from the repository are real; every number is invented for illustration. Weekly orders this year and checkout completion are 02Sparklines in prose.