In OSM objects have zero or more tags, a set of key/values (with both being strings). That's all. With that, the OSM community has come up with lots of ways to

In OSM objects have zero or more tags, a set of key/values (with both being strings). That's all. With that, the OSM community has come up with lots of ways to classify and tag things. e.g. the railway nerds have very detailed ways to tag railway infastructure: https://wiki.openstreetmap.org/wiki/OpenRailwayMap/Tagging https://wiki.openstreetmap.org/wiki/OpenRailwayMap/Tagging