Maps have always been tools of power. About 30 years ago, Bernard Nietschmann, professor of geography at Berkeley, warned people that, “Either you will map or you will be mapped.” Indeed, even if many people never realise it, whoever succeeds in making their map the default one of some area greatly influences what everybody else may learn about its history and culture, or propose to improve it, from wildlife management to land property reforms. That’s why Nietschmann always helped indigenous people to, quoting from his obituary, “chart their own fate”. The OpenStreetMap project, or OSM for short (https://openstreetmap.org), created in 2004, gives the same opportunity to every indigenous of our planet, first-world urbanites included. This tutorial, which is split into three parts, explains why and how you could do just…