Location search relies upon address data, which links latitude and longitude coordinates like 38.8976,-77.0365 to human-readable addresses like 1600 Pennsylvania Avenue. This is an important but underappreciated type of geodata, and one that existing open data projects like OpenStreetMap have had limited success at collecting.
Many governments publish address data, but they do so in different ways. The data can be distributed as a Shapefile, CSV, KML, ZIP or GeoJSON file, or via an API. It can be presented in a variety of different geographic projections and character encodings. The names of fields are not standardized: for example, longitude might be stored in a field called LONG, X, LNG or LON. The license terms associated with the data can vary. Sometimes the data points to specific houses and sometimes it is no more specific than property parcels. The data might come with useful additional fields, like ZIP code or city name. The type of