I've been searching for info about what the subject line describes. From the OSM Australian Wiki site https://wiki.openstreetmap.org/wiki/Category:Australia, I see that by choosing the Cycling option and then selecting Map Key, I get a contoured map with a straight-forward legend (e.g. https://www.openstreetmap.org/#map=16/-37.2846/144.2121&layers=C), which seems to broadly correspond to the way basic data is displayed in andrewp's excellent Australian OSM maps. (Unlike the wierd and wonderful legends that are on offer from the international OSM site I looked at initially, were a legend may include 88 different types of grass meadow!) There's one puzzling difference though, which I'm hoping someone can explain.
In the OSM Wiki legend above, all vehicular bush tracks are shown as brown dashed lines. For andrewp's Vic, NSW and SA maps, such tracks are shown as either brown or red dashed lines. What's intended by that distinction? I'm guessing that brown is 2WD and red is 4WD, but I'd like to be sure.
I guess also that I might as well ask one more question, given that the Map Key I mention above, being classified as Cycling, does have some data not relevant to bushwalking. Is there a way to get to a legend which is relevant?