WebGIS is the term for a geo information system (GIS) whose function is partly based on networking technologies (internet, intranet). If at least two computers are linked so that geo data can be exchanged and GIS functionality is ensured (client-server principle) then this constitutes a WebGIS.

In a simple desktop GIS setup, the client possesses both the geo data and the GIS functionality. When geo services are provided within a WebGIS architecture featuring a web browser as client, most of the work can be done by one or more servers; the functionality of the client is limited to the visualization of results (incl. navigation)