Delta between a web service and a web application

As shown in the following diagram, a web service essentially maps each of its features or resources as HTTP endpoints and serializes its data over HTTP.

In addition to handling these tasks, a web application also provides a user interface built with HTML, CSS, and JavaScript documents and supports the user session.

Differences in the concerns handled by the HTTP layer between a web service and a web application

This chapter shows you how to handle the concerns about the user interface. Session handling is covered in Chapter 6, Leveraging the Play Stack – Security, Internationalization, Cache, and the HTTP Client.