OpenStreetMap is a huge database of objects
all around the world. You can find there both countries and cities, and the
nearest lampposts and benches. Then you can make an application or use the data
for analytics. But "you can" does not mean "you can easily":
to get something out of OpenStreetMap, you need to know the materiel, you need
to know about the services, you need to be able to make geographical requests.
From this report you will learn how to make requests in Nominatim and Overpass
API, how to download OSM data and what to do with these files, and what PostGIS
has to do with it. Finally, we will deal with a one-hundred-page list of object
types: do we need to learn it by heart, or is there an easier way to find the
notation for the type you are looking for?