By now you should have a clear conceptual understanding of how each layer of the Web Interaction Model works to support the other layers. But practically speaking, how can we illustrate the actual request, return, and display of a Web resource?
The following link Web Transaction Process describes the Web Interaction Model with the Web process of requesting and receiving resources over the Web.

You will recall that one of the strengths of the Web Interaction Model is that it accounts for Signs and Metaphors as well as Information Architecture. These layers play a part by structuring the user's perception of the site. The first two layers create a system of organization that the user is able to interpret and interact with. The process would never be set in motion if the user did not have some design and organizational structure to interact with.
In the next lesson, you will learn how Web-based business applications are supported by the Web Interaction Model.

Web-based geographic applications are continuously evolving and are becoming increasingly widespread. However, designing these applications is still a cumbersome task because it requires multiple and high-level technical skills related not only to recent Web technologies but also to technologies dedicated to (GIS) geographic information systems. Due to this complexity, recent works highlight the difficulties to integrate sophisticated interactions in such applications. Our objective seeks to take the designers out of this complexity to allow them to focus their design activity on the interactive dimension of the application to elaborate. An adapted design model should be proposed as a framework allowing designers to create applications according to an interaction point of view. All these contributions have been integrated in a Web 2.0 prototype allowing designers to visually specify and implement web-based geographic applications.

Application design is often based on two essential complementary aspects: 1) data and 2) process modelling. This approach deals with identifying data involved in the application and the processes applied on these data. However, during the first steps of the application life cycle, the designer is not able to easily define the properties of these two complementary points of view.
With a user-centered design approach^[1], the first focus is on what users will see and on what they will be able to do with it. Resulting descriptions focus on what the application will display, how things will be displayed and how these things will react when users will interact with them. Typically, first descriptions look like this example: The application will display a text describing the travel and a map centered on the visited area. On a click on any town, any river or any mountain mentioned in the text, a zoom on the corresponding area will be carried out on the map and the text part describing the selected place will be highlighted." In the context of geographic applications, the user interacts with geographic data that can be presented in several ways. Generally the result of such kind of interaction deals with the calculation, the transformation and/or the presentation of new geographic data.

Click the Exercise link below to test and apply your knowledge of the Web Interaction Model as it describes an e-commerce transaction.
Web Process in Action - Exercise

[1] User-centered design: User-centered design is an iterative design process in which designers focus on the users and their needs in each phase of the design process.