Web mapping is the process of designing, implementing, generating and delivering maps on the World Wide Web and its product. While web mapping primarily deals with technological issues, web cartography additionally studies theoretic aspects: the use of web maps, the evaluation and optimization of techniques and workflows, the usability of web maps, social aspects, and more. Web GIS is similar to web mapping but with an emphasis on analysis, processing of project specific geodata and exploratory aspects.

Types of Web Maps:
1.Dynamic web maps

a.Realtime web maps
Realtime maps show the situation of a phenomenon in close to realtime (only a few seconds or minutes delay). Data is collected by sensors and the maps are generated or updated at regular intervals or immediately on demand. Examples are weather maps, traffic maps or vehicle monitoring systems.

b.Personalized web maps
Personalized web maps allow the map user to apply his own data filtering, selective content and the application of personal styling and map symbolization. The OGC (Open Geospatial Consortium) provides the SLD standard (Styled Layer Description) that may be sent to a WMS server for the application of individual styles. This implies that the content and data structure of the remote WMS server is properly documented.

c.Collaborative web maps
Collaborative maps are still new, immature and complex to implement, but show a lot of potential. Technically, an application allowing simultaneous editing across the web would have to ensure that geometric features being edited by one person are locked, so they can’t be edited by other persons at the same time. Also, a minimal quality check would have to be made, before data goes public.

2.Static web maps
Static web pages are viewed only with no animation and interactivity. They are only created once, often manually and infrequently updated. Typical graphics formats for static web maps are PNG, JPEG, GIF, or TIFF (e.g., drg) for raster files, SVG, PDF or SWF for vector files. Often, these maps are scanned paper maps and had not been designed as screen maps. Paper maps have a much higher resolution and information density than typical computer displays of the same physical size, and might be unreadable when displayed on screens at the wrong resolution.

Advantages of web maps
Web maps can easily deliver up-to-date information. If maps are generated automatically from databases, they can display information in almost realtime. They don’t need to be printed, mastered and distributed.

Examples:
•A map displaying election results, as soon as the election results become available.
•A map displaying the traffic situation near realtime by using traffic data collected by sensor networks.
•A map showing the current locations of mass transit vehicles such as buses or trains, allowing patrons to minimize their waiting time at stops or stations, or be aware of delays in service.