Tuesday, March 26, 2013

OpenStreetMap: the free wiki world map


Beginning


For hundreds of years, the military cartographic industry did its best to provide soldiers and their commanders with the best available location information, to be the ones who win the battle. Countries tried to make detailed maps of their neighbors’ land and to prevent neighboring countries from creating maps of their land. Some countries around the world succeeded. China, for example, is a country that still punishes its citizens — and others — when they use maps more detailed than the government allows.
By the end of the Cold War, the cartographic industry had to adapt to a new reality. Major wars were no longer being fought, and the mapping industry had changed a lot. Many details disappeared from maps. (Who pays for measuring the height of a hill? Only those who need to hide an expensive tank behind it). Other mapping details appeared for the first time. (Oh, we need postal code boundaries; we've got to know where to deliver pizza!)
Still, geoinformation doesn’t come cheap. The agency that collected the data keeps a tight hold on it in order to get more money from you. Oh, you want to scan the paper maps and put them into your personal digital device? Pay up!

Revolution

OpenStreetMap contains rather detailed models of buildings
Almost ten years ago, in 2004, a group of volunteers decided to break this monopoly and created OpenStreetMap project. Ideas behind it are much like the ones Wikipedia has: open data, accessible to and able to be edited by everyone, and Linus Torvald's Law: “given enough eyeballs, all bugs are shallow”.
After a couple of years of initial mapping by very addicted enthusiasts, it became the most advanced open map in the world. Here at MapsWithMe, we use this data to let you put these maps into your pocket device and not feel lost anywhere in the world, even without a network connection.

Open data

The idea that powers OpenStreetMap, Open Data, became so popular that many governments began allowing access to the information they had collected (United States, many european countries - see Wikipedia for the list: http://en.wikipedia.org/wiki/Open_data#Open_data_in_government). This information includes geodata, which found its new home in the OSM project, which is now being carefully monitored by more than a million mapping enthusiasts.
Don't think it's good in your area? Here's how it’s different from all other maps: you can improve it! Just open openstreetmap.org and click on the “Edit” tab at the top.

Tags system

TagInfo OpenStreetMap tags cloud
The main reason OSM has become so popular is because of its tags system - anyone can add any information they would like to.
Each object in OpenStreetMap, apart from coordinates, can have an infinite number of key=value pairs describing its properties. Tags can contain any information – from address data to the amount of street lighting, from routing restrictions to heights of buildings.

To make it easier to know which tags exist in the database, the community has created a special web site, TagInfo.

What do you think? Which tags are worth adding to our MapsWithMe map in the next release?