OCG Web Services are for retrieving and displaying geospatial data over the internet (Web).

An OGC Web Service is usually not invoked directly. More often, it is invoked by a geospatially aware client application that provides the user with interactive controls. This client application may or may not be web-based.

But because they are Web services they are also accessible in any Web browser. Firefox does a very good job of displaying XML, as does Internet Explorer, in most cases.

So we will examine several OGC based Web Services using a browser and examine how to examine and manipulate them by editing the URL's used to access them.

We will look at: WMS, WFS, SOS and then look at several tools which can also be used to explore Web Services.