Web mapping

Web mapping or an online mapping is the process of using, creating, and distributing maps on the World Wide Web (the Web), usually through the use of Web geographic information systems (Web GIS). A web map or an online map is both served and consumed, thus, web mapping is more than just web cartography, it is an interactive service where consumers may choose what the map will show.

The advent of web mapping can be regarded as a major new trend in cartography. Until recently, cartography was restricted to a few companies, institutes and mapping agencies, requiring relatively expensive and complex hardware and software as well as skilled cartographers and geomatics engineers.

Web mapping has brought many geographical datasets, including free ones generated by OpenStreetMap and proprietary datasets owned by Baidu, Google, HERE, TomTom, and others. A range of free software to generate maps has also been conceived and implemented alongside proprietary tools like ArcGIS. As a result, the barrier to entry for serving maps on the web has been lowered.

The terms web GIS and web mapping are often used interchangeably, but the terms are distinct. Web GIS uses and enables web maps, and end users who are web mapping are gaining analytical capabilities from Web GIS, however Web GIS has more applications than web mapping, and web mapping can be accomplished without Web GIS. Web GIS emphasizes geodata processing aspects more involved with design aspects such as data acquisition and server software architecture such as data storage and algorithms, than it does the end-user reports themselves. The term location-based services refers to web mapping consumer goods and services. Web mapping usually involves a web browser or other user agent capable of client-server interactions. Questions of quality, usability, social benefits, and legal constraints are driving its evolution.

A first classification of web maps has been made by Kraak in 2001. He distinguished static and dynamic web maps and further distinguished interactive and view only web maps. Today there is an increased number of dynamic web maps types, and static web map sources.

Analytical web maps offer GIS analysis. The geodata can be a static provision, or need updates. The borderline between analytical web maps and web GIS is fuzzy. Parts of the analysis can be carried out by the GIS geodata server. As web clients gain capabilities processing is distributed.

Realtime maps show the situation of a phenomenon in close to realtime (only a few seconds or minutes delay). They are usually animated. Data is collected by sensors and the maps are generated or updated at regular intervals or on demand.

Animated maps show changes in the map over time by animating one of the graphical or temporal variables. Technologies enabling client-side display of animated web maps include scalable vector graphics (SVG), Adobe Flash, Java, QuickTime, and others. Web maps with real-time animation include weather maps, traffic congestion maps and vehicle monitoring systems.