The Global Positioning System (GPS) provides geolocation. Note that strictly speaking GPS only refers to the positioning system operated by the United States and that it is actually just one of several global navigation satellite systems (GNSS) ... others are for example Galileo, GLONASS and BeiDou. Colloquially people however just tend to say GPS and are often unfamiliar with GNSS. For the same reason the web front end also just speaks of GPS traces.
A good way to get involved in the OpenStreetMap project is to upload GPS traces. Recorded by your satellite receiver or mobile phone, the typical trace is a record of your location every second, or every meter (“tracelog”). Convert it to GPX format if it wasn't done for you automatically. The collected data can be displayed as a background of thin lines or little dots within the map editor. These lines and dots can then be used to help you add map features (such as roads and footpaths), similar to tracing from aerial imagery.
- Record tracelog – The basics of different types of device, and how to record a tracelog.
- Convert to GPX – (optional) A simple process that may be required before you can upload your traces.
- GPX – Presentation of the (XML-based) GPS/GNSS data exchange format used by OpenStreetMap.
- Modify tracelog – (optional) For a variety of reasons, you may want to modify a tracelog before uploading it.
- Upload – How to upload a GPX file to the OpenStreetMap website and some common problems that might occur.
- API v0.6#GPS traces – Technical documentation of the online API to submit and query GPX data to OpenStreetMap servers.
- Accuracy of GPS data – The accuracy of GPS data depends on many factors.
- GPS device reviews – If your thinking of getting a GPS Receiver to add data to OSM these device reviews are here to help.