Geographic Information Systems: crowd-sourced spatial data

This article covers concepts related to geographic information systems (GIS), focussing on the characteristics of the data such systems process, i.e., spatial data. In particular, it discusses the new phenomenon of crowdsourcing and how it has affected spatial data production and use. The most popular crowdsourcing project in the spatial domain, namely, OpenStreetMap (OSM), is analysed including an overview of the research literature that investigates the characteristics of its data. Issues related to the quality of OSM data are also the focus of much attention from the research community and are reviewed here