Some map makers have found a way to draw people to their detail-oriented field: have a party.
It involves replacing beer -- at least for part of a day -- with a GPS (Global Positioning System) unit to build on OpenStreetMap, a project that uses volunteers to map the world. It's a community-led approach, drawing on the same kind of unpaid passion that fuels development of the Linux operating system and resources such as Wikipedia.
Much of Western Europe and the US have now been mapped by volunteers. An increasing number of people are coming to so-called mapping parties, where a group maps a particular area with hand-held GPS units, said OpenStreetMap founder Steve Coast.
Coast, 28, of London, started OpenStreetMap in 2004 when he was a physics student at University College London (UCL). Coast said he became interested in GPS and mapping, but was surprised to find how closed the field is: a handful of companies control much of the geodata that exists, and that data is very expensive to use, with many copyright restrictions.
The reason why is that mapping data is very expensive to collect. "That's quite a high barrier to entry that stops competition in the geodata market," Coast said.
In the early days, Coast wrote the software for making maps, answered questions and did a lot of talks at open-source conferences and technology events to create momentum around OpenStreetMap. The idea caught on. People in other European countries were also disenchanted with the high cost of geodata, Coast said.
OpenStreetMap is now growing on work of those volunteers. Registered users of the OpenStreetMap Web site now tops 85,000 people. At a mapping party, novices are instructed on how to use a GPS unit, which records "trace" data, or a list of points along a path.
When plugged into a PC, the trace data can then be labeled as anything -- a road, a footpath, a cycling path, a postbox, a landmark. It also gives vector data, which is key for creating accurate routing directions and journey time estimates, Coast said. That data is then integrated into OpenStreetMap.
Mapping "really does scratch an itch," Coast said. "When one person sees a map that's wrong, it's very addictive, and people start filling in all the detail."
The result has been sets of very detail-rich maps, some of which are focused on specific interests, such as OpenCycleMap.org. It's essentially the core data from OpenStreetMap but with a different cartographic style to highlight bike routes.
The flexibility for users to do what they want with OpenStreetMap comes from its Creative Commons license, Coast said. People can modify the data and publish new maps, but those new maps must be published under the same license as OpenStreetMap. Also, data taken from OpenStreetMap must be attributed in the new derivative work, Coast said.
OpenStreetMap has also seen large companies donate to the project. Yahoo has lent use of aerial imagery, which allows people to mark points at home without GPS, Coast said. A Dutch company, Automotive Navigation Data (AND), donated road data for the Netherlands. OpenStreetMap is a nonprofit and other organizations have donated GPS equipment. UCL donates Web hosting.
Why would those companies give away their data? Coast said it's a combination of wanting a bit of good press but also a desire to be active in next-generation mapping systems. AND is one of the few established mapping companies that is forward-looking and not hoping services such as OpenStreetMap and Google Maps fade away, Coast said.
As it grows, OpenStreetMap could soon threaten established companies by essentially commoditizing what is now highly valuable geodata, particularly at the bottom end of the mapping market, Coast said. However, there will always be demand for specialist maps, such as surveyed data used by utility companies when digging new gas or phone lines, he said.
Coast and his partner Nick Black have also co-founded a for-profit business, CloudMade, on the back of OpenStreetMap. CloudMade offers mapping data that's based on the volunteer data coming into OpenStreetMap but has been verified to be correct and free of errors. Those maps are hosted on separate servers, and clients get service-level guarantees, among other services.
So far, OpenStreetMap hasn't been integrated into an in-car device, partly since it is still compiling complete maps for countries.
"OpenStreetMap needs to reach the point where we have larger areas covered," Coast said. "But it's not far off."
OpenStreetMap will hold its "State of the Map" conference in Amsterdam from July 10 through 12. In London, OpenStreetMap has a couple map parties planned, one on Feb. 4 and Feb. 18. OpenStreetMap also has a Web page dedicated to tracking the mapping efforts in many countries.