Points of Interest

OpenStreetMap is an amazing project. Almost without any leadership, thousands of people put their efforts together to create the most up-to-date and most detailed geo database ever. Here’s my inofficial, work-in-progress FAQ about some of the “secrets” that glue the project together.

Q: Is it true that in OpenStreetMap, anyone can add objects and annotate it with any free text tags?
A: Yes, that’s exactly how it works.

Q: Doesn’t it lead to chaos if anyone can just map anything?
A: Obviously not. There are some strangely tagged objects in the database, but most people just use the tags used by others. There is Tagwatch which gives a good overview. A major influence comes from renderers and routers – mappers just tend to use items that either of them understands.

Q: In Tagwatch, I see items such as park benches, waste baskets or even hunting stands. Shouldn’t such stuff be removed from a street map?
A: The name is sort of understatement. OpenStreetMap is nothing more or less than a giant geodata database. Besides streets, you will find restaurants, post boxes, pharmacies, shelters and well, even hunting stands. The openness is one of the huge advantages, as it allows to (ab)use the openstreetmap database for specialized usages like OpenPisteMap.

Q: There is a complex process of proposals and votings in the wiki. What is it all about, especially compared to Tagwatch?
A: Only a small part of all mappers take part in this process. Some votings count about 15 to 20 votes – out of over 50.000 mappers. It is an interesting indicator what some people think about tagging. But voting results are not binding for anyone, people can still tag whatever they like.

Q: Map Features seems to be the holy grail of openstreetmap tags. Are those tags updated regularly to reflect what people are actually using?
A: In the optimum case, we would maintain Map Features this way. It does not happen often enough to reflect reality, though. This mainly has two reasons. First, there are simply not enough people who care about it. Second, many people think that Map Features must not be changed except as a result of the voting process. That’s a misperception.

Q: Who can officially speak for OpenStreetMap?
A: Noone. OpenStreetMap just is an informal organisation of enthusiasts, open for anyone.

Q: What is the openstreetmap foundation?
A: This is a non-profit organisation based on british law that tries to help openstreetmap.org with fundraising, press work and the like. Though it is theoretically independent from openstreetmap.org, there is a certain mixture of people who are part of both projects, of course. In the medium turn, we will surely see similar organisations in other countries, too.

Q: I want to map a feature that is not yet in Map Features. Where do I have to submit the proposal for addition of a new feature?
A: Nowhere. Just think of something that makes sense and use it. After you have used it for a while, you can still write a proposal if you want. At OpenStreetMap, we think that it is often a waste of time to discuss stuff before people have even used it.

Q: But I want my new feature to be voted on so that it will show up on the map!

A: With Openstreetmap, there is no “the map”. Everyone can make their own maps from Openstreetmap data, and if you do, then you decided what is on the map and what isn’t.
The maps we display on openstreetmap.org are one way of making maps from our data; they are intended as an example, a show-case of our work. What is shown or not shown on these maps is not determined by votes or the “Map Features” list; it’s solely the programmers of rendering software and the style designers who decide. If you’re unhappy with what they do, then join them and help make it better!

Q: What sense does it make to have all these things in the database if they don’t show up on the map?

A: If you want a map that shows everything, you can make one. The maps on openstreetmap.org are designed to look halfway decent, so it is not always possible to include every detail on them lest they would become too cluttered.

Q: How does OpenStreetMap decide what’s right and what’s wrong if there is a dispute?

A: OpenStreetMap doesn’t. OpenStreetMap is very much based on avoiding disputes whereever possible. The open tagging schema allows people to tag the same object in multiple ways if they cannot agree. Things that have different names can be tagged with all the names desired. There is no need to do everything the same way everywhere on the planet (although it makes some things easier).

Q: But you must have rules about what is accepted in the database and what isn’t!

A: Rules, no, we don’t have them. We generally allow everything in the database, and put the burden of filtering on the user. It’s like the Internet – anyone can put anything online, and if you’re looking for something then you need to filter the content.
That being said, there *is* a line between what people think is worth mapping and what isn’t, and that line is largely based on how long information is likely to be valid and whether or not there is a realistic chance to keep it current. So yes, we would map individual trees, but we’d probably not map individual flowers. But this is just a vague line, not something set in stone.

Q: Can’t you complete the mapping of important things like motorways before you start entering footways and post boxes?

A: Openstreetmap mapping does not proceed according to a master plan – we have nobody to set up such a plan, and we have nobody who would pay employees to follow it. Our mappers are motivated by what is important to *them*. A cyclist is unlikely to map a single motorway, but we value his input even if his country doesn’t have a single motorway mapped. In a way, Openstreetmap often has “depth-first” mapping rather than “breadth-first” mapping.

Q: Doesn’t it make the data difficult to use if the tagging schema is constantly updated, modified, amended, and not even applied evenly across the planet?

A: Yes – OpenStreetMap requires the user of data to know or find out his share about the data; it doesn’t come on a silver platter. OpenStreetMap is geared towards serving the needs of mappers – they are the heart and soul of the project, and they get to decide what is put in the data base and how. Imposing too many rules on them would reduce mapping from a fun and creative activity to a dull and boring data collection task.
We give our data away for free, and if our users need more structure, they can convert our data to match their needs.