Participatory GIS projects usually involve collaboration, which in turn requires the sharing of geospatial information. Until recently this often meant that data files needed to be converted from one system’s internal format into that of another system.
To overcome these ‘non-interoperability’ problems, the Open Geospatial Consortium (OGC) and ISO Technical Committee 211 (ISO TC/211), together with geospatial technology vendors, have developed a set of standards for open interface and encoding specifications. By applying these standards in their products, vendors can now offer geoprocessing software systems that can access data regardless of where and how they are stored.
The OGC standards open up many new opportunities for GIS projects. For example, with the OGC’s OpenGIS Web Map Server (WMS) anyone with an ordinary web browser can call up multiple overlaid thematic maps. The maps may be generated by different servers at different sites running different software. This integrated access is possible because the OGC’s standards have been applied in these systems.