The main emphasis of the book is on practical methods rather than a theoretical one. The author highlights relevant information; skills and techniques needed in the process of designing of an attractive and efficient interface. Several factors affecting the design, efficiency and usability of User interfaces including common errors made are highlighted throughout the book.
By dividing the book into five (5) chapters, the author is able to clearly examine Graphic User Interface's (GUIs). All the chapters of the book are coherent and not isolated or independent in topic content. He proposes incorporating fundamental principles for industrial and domestic designs and their concept to the Graphic user interface design. These principles are broadened through levels increasing from the most theoretical to practical using examples of various graphic user interface implementation on a windowing platform such as in Windows; the Apple Mackintosh (Mac), Motif and other X-Windows based systems. A GUI designer team should possess relevant skills such as Graphics design, System Analysis, Cognitive and Task Engineering skills.
I. Fundamental principles of design: the first principle states 'simple tasks deserve simple interfaces' while the second principles similarly states that 'complex tasks demand guidance and elucidation'. The ability to differentiate between complex and simple task is easily acquired by learning from feedbacks or experiences of users. Using the Microsoft Word version 6.0 which has undergone considerable revision as a case study, the author concludes that the certain factors such as Visibility, Feedback, and Mapping & Affordances as not totally disjoint components of design but highlights them as the elements of design. He states that the absence of these factors leads to many errors in design. A good User Interface supports cognitive processes such as memory and learning while avoiding overloading shift memory. A combination of principle is intended to lead to even greater effectiveness and satisfaction to the user.
II. Conceptual models: The use of a strong model is the foundation for designing an effective Graphic User Interface. Using the Mac and Microsoft windows models of faxing as case study, Zetie explores the ideas of models and their transformation in considerable detail. He writes that though 'a model should contain a point of reference (a center)' and a 'domain of expressions' they should not be limited by these referent models". The choice of models is therefore of importance to the success or failure of a good user interface.
III. Task flow: Through the use of various illustrations and the Lotus Freelancer version 2.0 as case study, the Author discloses that Good task flows are characterized by certain guidelines including the elimination of unnecessary restrictions and making hidden dependencies visible through expressing constraints.
IV. Dialog design: Using a Stock control application system as case study, it is seen that dialog design should support task flow. A dialog flow is the mechanism that is used to control or manage task flow. This chapter also highlights the dialog notation which provides an effective