When typing in the JOSM preset search (F3) and key road the result is the screen selection below. The highlighted “Unknown Type” which leads to the tag generation of highway=road. TagInfo shows this having has been applied 75 thousand times, but has no text explaining what it is.
IIRC ID or StreetComplete complain about this tag and JOSM pops the “unspecific highway type” warning, the chronology actually showing the number is reducing from a high of near 500 thousand i.e. is being corrected. Maybe the JOSM preset should be fixed to highway=unclassified?
I am not sure whether I get you right. What is the problem?
Although highway=road should be avoided if possible, it is correct tagging. And it is definitely not equivalent to highway=unclassified.
highway=unclassified does NOT mean the type/category of a road is unknown. The name unclassified is an artifact of the origin of the road classification system in OSM, which is based on the classification system of the UK since that’s where OSM started. Please see the wiki for details.
If you really don’t know the type of road, then “highway=road” is correct. However, even using aerial imagery and comparing to similar nearby roads, these days it’s usually possible to have a pretty good guess.
To my surprise there’s an actual highway=road wiki though the TagInfo result makes no link and the wiki does say
Treat it as an error
Mappers and mapping software should treat it as an error when a way is tagged with highway=road. Mapping software can issue warnings to make sure the mapper really does not know the road type. The error is fixed by using the correct road classification.
