Despite its name, OpenStreetMap is a database in a first place. And openstreetmap.org provides more or less informative page for each object in contains - way, node or relation. For example, look at this way: osm.org/way/80476600 - it’s the Millennium Oakwood park, located at the Isle of Man.

Nowadays, if someone wants to find something on the Web, the most obvious way to do that is to use a web search. Such as Google, for example.

Let’s search for “Millennium Oakwood”. Google Maps widget goes first, couple of government sites following it, someone’s photo on Flickr and tons of rubbish.

Let’s do it more straightforward: “Millennium Oakwood OpenStreetMap”. No Google Maps, but other results are quite similar. One exception - couple of entries from triposo.com, which uses OpenStreetMap.

So, basically, there is no way to find an object in OSM database via web search updated: for general public, who have no intention to query OSM data specifically.

Non-searchable = non-existent, at least, for people, using text search on the web.

I can imagine, that someone can argue, that OSM shouldn’t display its “guts” - lists of nodes, links to changesets and so on. But actually, many of these pages somehow were indexed by search engines and you can find at least a fraction of them.

I don’t know, if current rules of robots.txt file (which tells search engines what not to index) are actually preventing it, or there is another reason for it. But currently, the whole bunch of information in OSM database is just completely hidden from public searches.

For me, it seems like talking about informing people of OSM and hiding it from them in the same time is a kind of self-contradiction.

OpenStreetMap has many tags, inherited from a natural language with blurred meaning and definitions, depending on each mapper’s understanding of associated natural language term. Also, many tags are representing more than one property of an object, such as, say, type of flora, populating particular area and presence of management of this area. (Good example is natural=grassland and landuse=grass.)

In an ideal case, any classification system should have only “atomic” properties instead of “molecular”, where several real properties are linked. (Good example is the recently introduced scheme with leaf_type= and leaf_cycle= - independent properties instead of linked ones.)

One of the extremely widespread tags with both bad features is natural=wood.

It belongs to natural=* class, and it gives people an idea, that only natural habitats should be tagged with it. Therefore, we also have landuse=forest, which means the same kind of habitat, but more related to man-made objects.

Actually, it creates the really huge problem. First, let’s try to explain what exactly we should map with it.

Both natural wood and any kind of planted forest are areas of vegetation, dominated by trees. But there is no clear definition (in OSM), what does “dominated” mean.

natural=wood should, supposedly, tells us, that area of vegetation forms “natural habitat”. But there is no clear explanation, what does “natural” mean.

landuse=forest should, supposedly, tell us, that area of vegetation is managed, or planted, or forms artificial habitat, or trees there are non-native. There is no clear explanation, is there any difference between landuse=forest and landuse=plant_nursery - difference is only implied, because nursery should be only used to plant young trees for sale or for planting it somewhere else for forestry management purpose.

So many variants, so many assumptions and lots of guessing.

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