Formchart of an Example Online Bookshop

A formchart depicts a user interface model. It consists of client pages, server actions, and the transitions between them. Client pages are depicted by ellipses, server actions are depicted by rectangles, transitions are depicted by arrows. The example formchart below is taken from the book "Form-Oriented Analysis" (Fig.5.2, page 56). It models some crucial features of a simple online bookshop: browsing categories, search facility, shopping cart, buying, registering a new customer, login. A formchart depicts only a part of a form-oriented information system model, i.e., the dialogue model. The dialogue model is integrated with a layered data model and a dialogue specification.