Getting on the map

摘要

Nobody has yet called the police about Jerry Clough, but he gets strange looks. Strolling around Nottingham, he takes photographs seemingly at random, jotting notes and mumbling about missing numbers. Mr Clough is one of a handful of Britons who collect addresses for Open-StreetMap (osm), a global group of volunteer cartographers who maintain free online maps. "Yes, it is a bit obsessive," he says. "But it makes our maps much better." Addresses have always been important in the real world: among other things, they help establish people's identities and guide emergency services to where they need to be. They increasingly matter in the virtual world, too, as websites and apps rely on them to give directions, send users to the nearest cinema or cheapest petrol station, and more. An accurate and detailed address book that includes geographical co-ordinates is turning out to be the connection that binds the digital and physical realms together.