What’s a web map service?

A web map service (WMS) is a CGDI-endorsed standard to provide visualization of geospatial data over the Internet. A web map service allows you:

• To consume (or view) information on a map online—either from several different maps at a time or as a single customized map with overlaid views from different sources—by connecting to a web map server; and
• To publish (or provide) a map layer from your GIS or image processing system onto the Web for others to see. A web map service also allows you to provide views of your metadata so that clients can picture the data or products you are responsible for.

To view a popular web map service, see the Atlas of Canada.

To see a web map service in action, see North American Weather Today.

For a listing of other web map services, see the GeoConnections Discovery Portal.

To read more about web map services,see GeoPlace.com.

Before you start It is important to distinguish between a view of a map and the actual map itself. A web map service lets you view a dynamic image of a map, which is stored and maintained at the provider’s site; a map from the Atlas of Canada, for example, resides on the Atlas of Canada server. In other words, when you create a map on your computer screen, you are viewing a particular piece of geospatial data at a particular point in time, but it is not stored on your computer. With web map services, you can find, view and customize all the geospatial data you want, without having to maintain it.