Web mapping is the technique of utilizing maps that are obtained by a geographic information systems (GIS) for spatial and geographical data. A web map on the World Wide Web is both served and consumed, thus web mapping is more than just web cartography, it is a service by which users may choose what the map will show. 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 terms web GIS and web mapping remain somewhat synonymous. Web GIS uses web maps, and end users who are web mapping are gaining analytical capabilities.
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 Google, Bing 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.
for more information on web mapping visit the following links:
https://www.e-education.psu.edu/geog585/node/643
https://www.e-education.psu.edu/geog585/node/519
References
Plewe, B. (1997). GIS online: Information retrieval, mapping, and the Internet. OnWord Press.