Web mapping is the process of designing, implementing, generating and delivering maps on the World Wide Web. Dissemination via the web opens new opportunities: realtime maps, cheaper dissemination, more frequent and cheaper updates, personalized map content, distributed data sources and sharing of geographic information. Technical restrictions cause challenges like low display resolution and limited bandwidth,( in particular with mobile computing devices with small screens and using slow wireless Internet connections), copyright and security issues, reliability issues and technical complexity. Today's web maps can be interactive and integrate multiple media. So interactivity, usability and multimedia issues also play a role.