OpenStreetMap uses tags to add meaning to geographic objects. There is no fixed list of those tags. New tags can be invented and used as needed. Everybody can come up with a new tag and add it to new or existing objects. This makes OpenStreetMap enormously flexible, but sometimes also a bit hard to work with.
Whether you are contributing to OSM or using the OSM data, there are always questions like: What tags do people use for feature X? What tags can I use for feature Y so that it appears properly on the map? Is the tag Z described on the wiki actually in use and where?
Taginfo helps you by showing statistics about which tags are actually in the database, how many people use those tags, where they are used and so on. It also gets information about tags from the wiki and from other places. Taginfo tries to bring together all information about tags to help you understand how they are used and what they mean. See a list of sources taginfo uses.
Building on taginfo
You can use the data from taginfo in your own projects:
Taginfo data can be accessed through a REST API. See the API documentation for the details, some general information is on the OSM wiki. The servers running the taginfo API do not have unlimited resources. Please use the API responsibly. If in doubt contact the maintainers of the site you are using or talk to us on the mailing list.
If you want to play around with the data used by taginfo, you can download the regularly updated Sqlite database files. All the preprocessing is done for you. See the download page for a list of files. Note that some of these files can get quite large. If you want to download them regularly, contact the maintainers of the site you are using or talk to us on the mailing list.
The data available through taginfo is licenced under ODbL, the same license as the OpenStreetMap data.
The taginfo software
Running your own instance
Bug reports and feature requests
Bug reports and feature requests should be directed to the GitHub issue tracker. Or you can come talk to us on the mailing list.
Contact us on the taginfo-dev mailing list if you have questions or want to help.