Chameleon is an open source, distributed, highly configurable, environment for developing Web Mapping applications. It is built on MapServer and supports MapServer supported data formats. It also works well with OpenGISConsortium standards for Web Map Services WMS and Web Map Context Documents (WMC) through MapServer’s support for these standards.
Chameleon was originally developed in 2002 by DM Solutions Group under contract to NRCan , in support of Canada’s GeoConnections program, contributing to the Canadian Geospatial Data Infrastructure (CGDI). Originally named “CWC2” (CGDI WMS Client Component), Chameleon was renamed to the open source community. CWC2 was developed in response to the growing number of WMS servers and lack of user friendly WMS clients in developing web mapping applications.
Chameleon has a plugin architecture. A large number of plugins, or widgets as they are called by Chameleon developers, are available. A Chameleon widget can implement a mapping task such as zooming, panning, showing legends, or displaying map coordinates. Over a hundred widgets are distributed with the application and developers can easily create their own widget for any specific task.
Chameleon is released under the BSD License . 
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