Summary

Three-dimensional visualisation on the Internet is mostly associated with VRML-browsers (Virtual Reality Modelling Language). The formats for three-dimensional visualisation are continuously improved, and it is possible to render geo-referenced data through GeoVRML. These two formats can be used on a standalone computer as well as over the Internet. Thus, three-dimensional visualisation on or off the Internet is quite the same. The only things that are special for Internet visualisation are the limited transfer and access time, protocols, and server based-solutions. Three-dimensional visualisation is sometimes erroneously called Virtual Reality. Virtual Reality is three-dimensional visualisation supported by special devices, and a “true” Virtual Reality system has 100% immersion. In the forthcoming text, the fundamental definitions of geometric primitives, three-dimensional visualisation, Virtual Reality, formats, and Internet visualisation are explained. The fundamentals are also put into a context and a usage perspective. In the future, the Internet visualisation will be used to explore questions and to collaborate at distance. An important force will be location-based services and mobile Internet, which could be used for explanatory sightseeing, world heritage presentations, games, construction, design, rescue training, modelling, analyses, and navigation systems.