## 2 General Context: Geocollaboration in the GeoWeb 2.0 Era
### The Wikification of Geographical Information  
The combination of collaborative work approaches together with geographic information is still limited on the GeoWeb 2.0. On the one hand, Wikis evolve and converge towards more collaborative and participative tools. Yet, the spatial component is either lacking (most commonly), or confined to the localization of content in order to spatialize information (geocoding, geotagging, geonaming, _etc._). The logic of Wikis is thus restricted to written contents. On the other hand, online mapping applications on the GeoWeb (Web map services, virtual globes) pay little or no attention to the collaborative aspect of contributions. Most of the time, users can only read, create and modify contents with no access to their versioning (neither read nor create access). Moreover, the existing solutions that provide versioning of contributions such as Google Map Maker, Wikimapia or OpenStreetMap are not effective in maintaining the traceability of geometric components to facilitate collaborative work. These applications are unable to maintain the history of contributions and edited objects (from original to final version) with all their components (geometric (location and form), graphic (iconography) and attributive (description of the object). They manage attributive components only. Yet, collaborative work requires knowing the following: Who has made changes in preceding versions? When and where were these changes made? Why and what for? How and what are the justifications? This is especially the case in asynchronous working contexts, or when projects are carried out over long periods of time, and with different frequencies. However, even in environments such as Wikimapia, in which the wiki dimension is emphasized, collaboration in the strict sense only takes place at the level of the descriptive components (text, hyperlinks, photos). Moreover, in most wiki applications there is no information available on users (their technical skills or degree of knowledge for instance) nor on their actions, except in Google Map Maker, Wikimapia or OSM. Developing a WikiGIS application that enables tracking of the history of spatial data edits and promoting geocollaborative working is fair. There are currently no examples of where this is done satisfactorily. Therefore, we have designed a new type of online collaborative mapping application based on the operating principles of Wikis, both in terms of creating and enriching location-based contents (of the map), and in terms of maintaining a documented history of all the stages of development. In the WikiGIS, location-based contents can be modified, enriched, updated and deleted by any user. All of the users' actions are saved, \"versioned\" and dynamically accessible via the content history. Storing all actions is a way to tell the story of the map (or project) \"in progress\". It allows the reporting of its progress over time or to \"rewind\" the process so as to understand its genesis, for example. The core component of wiki approaches is the process itself (data generation, map design), more than data, which are to some extent a materialization (an occurrence) of the contributors/actors' points of view (opinions). Contrary to most existing mapping mashups, in which users cannot really act on the database, the architecture proposed for the WikiGIS (cf. Section 3) ensures the traceability of the spatio-temporal evolution of each geographic object created, and provides dynamic access to the corresponding history file. Consequently, data coproduction could be achieved iteratively rather than in a cumulative way as in traditional GIS approaches. This new form of geo-data coproduction is interesting for geocollaborative work, when everyone contributes (expressing personal views) to a common project. Cartographic representation thus becomes a tool to read the dynamics at work in the production of spatial knowledge, and to keep track of spatial representations.