Difference between GIS and OSM data model
Meet the tags
The most striking difference is the way attributes are stored in OSM: not in a separate table, but through an open tag system, consisting of two free format text fields ('key' and a 'value') associated with each element. The OSM tag key identifies "a topic, category, or type of feature" whose value is specified in the "value" attribute, e.g. amenity=drinking_water to describe a point on the map, that marks a fountain with potable water.
What is fascinating is that the tagging schemes are open and determined by vague community consensus (read more on the OSM community and how they communicate here) which can yield confusing results (read up on the power=station fiasco, or highway=cycleway)
Comparing GIS shapefiles and OSM data
| GIS | OSM | |
|---|---|---|
| Free data updates | ❌ | ✅ |
| Globally unique object IDs, attribute definitions | ❌ | ✅ |
| Version control through community | ❌ | ✅ |
| Combining geometries in one format (points, lines, or polygons) | ❌ | ✅ |
| XML data format | ❌ | ✅ |
| Owner controls data | ✅ | ❌ |
| Bottom-up (crowd controlled) | ❌ | ✅ |
| Data license | Variable | ODbL |
GIS data for OSM or vice versa
You have geospatial data.
👉 Here's more info on what type of data makes sense to add to OSM and how.
Interested in crowdsourced OSM data?
👉 Read on here to learn about tools to extract the data you need from the global OpenStreetMap database.