OpenStreetMap is a free, editable map of the whole world that is being built by volunteers largely from scratch and released with an open-content license. The OpenStreetMap License allows free access to our map images and all of our underlying map data. The project aims to promote new and interesting uses of this data. OpenStreetMap powers map data on thousands of web sites, mobile apps, and hardware devices.
The map is built by a community of mappers that contribute and maintain data about roads, trails, cafés, railway stations, and much more, all over the world. OpenStreetMap emphasises local knowledge. If everyone maps their neighbourhood, then all we need to do is have one person in every neighbourhood joining the project! The community is diverse, passionate, and growing every day. Our contributors include enthusiast mappers, GIS professionals, engineers running the OSM servers, humanitarians mapping disaster-affected areas, and many more.
Similarly you'll see a diverse range of events, whether it's a gathering of outdoor enthusiasts getting together to map an area, a humanitarian remote-tracing mapathon, a user group for people working with map data, a technical hack-weekend, or many other event formats besides. The OpenStreetMap Foundation also holds a large annual international community conference called "State Of The Map". Many spin-off country or continent-sized regional conferences are organised at a more local level.
The most "central" all-encompasing list of events is maintained on the OpenStreetMap wiki: wiki.openstreetmap.org but we also have many on meetup.com, some of which are *not* listed there. Perhaps we should try to list some here on OpenTechCalendar
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