Skip to main content

A Web Map Service (WMS) is a standard protocol for serving georeferenced map images over the Internet

WMS is a widely supported format for maps and GIS data accessed via the Internet and loaded into client side GIS software.

It also specifies a number of different request types, two of which are required by any WMS server:

  • GetCapabilities - returns parameters about the WMS and the available layers
  • GetMap - with parameters provided, returns a map image

Optionally (within the strict standard), WMS may also support

  • GetFeatureInfo - with parameters provided, returns attributes from the data at a point location.

WMS may offer any number of vendor specific operations which will be declared within the GetCapabilities response, an example of a vendor specific operation is:

  • GetStyles (MapServer)

Commonly, WMS servers have some Styled Layer Descriptor (SLD) capability, such SLD enabled WMS may support the following operations:

  • DescribeLayer
  • GetLegendGraphic

OpenGISĀ® Web Map Server Implementation Specification

Styled Layer Descriptor profile of the Web Map Service Implementation Specification