DESIGNING THE USER INTERFACE ., o C -::0 --f ::c m o --f o Z CJ) -! ::0 » -! rT1 Ci) Congratulations! .nevvcopyotOesigning the User Interface, Fourth Edition. Your textbook includes six month$ of prepaid access to the book's Companion Website. This prepaid sUbscription provides yoU with fullaccessto all reader resourCes,including: Links to hundreds of HCI reso urces, examples, and research, which enhance and expand upon the material in each chapter. lIII Self-assessment questions.
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Library of Congress Cataloging-in-Publication Data Shneiderman, Ben. Designing the user interface: strategies for effective human-computer interaction / Ben Shneiderman, Catherine Plaisant. Includes bibliographical references and index. Human-computer interaction.1--dc22 2003068940 Copyright © 2005 by Pearson Education, Inc.
All rights reserved. No part of this publication may be reproduced, stored in a retrieval sys- tem, o~ transmitted, ~n any. form or by any means, electronic, mechanical, photocopying, recordmg, or otherwise, wIthout the prior written permission of the publisher. Printed in the United States of America.
ISBN 0-321-19786-0 1 2 3 4 5 6 78 9 1O-QWT-08 07 06 05 To Jenny and Peter; Anna, Sara, and Thomas Preface Designing the User Interface is written for students, researchers, designers, man- agers, and evaluators of interactive systems. It presents a broad survey of how to develop high-quality user interfaces for interactive systems. Readers with backgrounds in computer science, psychology, industrial engineering, informa- tion science, information systems, business, education, and communications should all find fresh and valuable material. Our goals are to encourage greater attention to usability issues and to promote further scientific study of human- computer interaction.
Since publication of the first three editions of this book in 1986,1992, and 1998, practitioners and researchers have grown more numerous and influential. The quality of interfaces has improved greatly, but the community of users and their diversity has grown dramatically. Researchers and designers could claim suc- cess, but user expectations are higher, applications are more demanding, and the variety of platforms has grown. In addition to desktop computers, designers must now accommodate web-based services and mobile devices.
At the same time, some innovators provoke us with virtual and augmented realities, whereas others offer alluring scenarios for ubiquitous computing, embedded devices, and tangible user interfaces. These innovations are important, but much work remains to improve the experiences of novice and expert users who still struggle with too many frustra- tions. These problems must be resolved if we are to achieve the goal of universal usability, enabling all citizens in every country to enjoy the benefits of these new technologies. This book is meant to inspire students, guide designers, and pro- voke researchers.
Keeping up with the innovations in human-computer interaction is a demand- ing task. Requests for an update to the third edition began shortly after its publi- cation. The growth of the field has encouraged me (Ben Shneiderman), the author of the first three editions, to work with a co-author (Catherine Plaisant), who has been a long-time valued research partner. We harvested information from books and journals, scanned the World Wide Web, attended conferences, and consulted with colleagues.
Then we returned to our keyboards to write. Our first drafts were only a starting point to generate feedback from colleagues, practitioners, and students. The work was intense, but satisfying. We hope you will put these ideas to work and produce innovations for us to report in future editions.
vii viii Preface New in the Fourth Edition Readers will see the dynamism of human-computer interaction reflected in the substantial changes to this fourth edition. The good news is that most universi- ties now offer courses in this area and some require it in computer science or other disciplines. There is still some resistance, but courses and degree programs in human-computer interaction are a growing phenomenon at every level on a worldwide basis. Corporate and government commitment to usability engineer- ing grows stronger daily, although many usability practitioners must still fight to be heard.
The business case for usability has been made repeatedly and whole Web sites describe scores of studies demonstrating strong return on investment for usability efforts. Comments from instructors who used the third edition were influential in our revisions. The main change was to delete the chapter on the World Wide Web and instead describe Web-based, desktop, and mobile device designs throughout. Every chapter is updated with fresh ideas, examples, figures, and references.
The opening chapter addresses the growing issue of ensuring universal usability for increasingly diverse users of interactive systems. Then guidelines, principles, and theories are substantially updated to reflect new ways of thinking. Part II covers the refinements to development methodologies, evaluation techniques, and software tools. Part III presents progress in direct manipulation and its extensions such as virtual and augmented reality, as well as changes to menus, form fillin, and command languages brought about by the new platforms, espe- cially consumer electronics devices.
Since collaborative interfaces have become so central, this chapter is moved forward in the book. Part IV emphasizes Quality of Service and a series of important design issues. Since user manuals and online help are vital to serve the goal of universal usability, that chapter is thoroughly revised. Finally, information search and visualization get special coverage since we believe that these topics will continue to grow in importance.
We strive to give balanced presentations on controversial topics such as 3D, speech, and natural language interfaces. Philosophical controversies such as the degree of human control and the role of animated characters are treated care- fully to present fairly the viewpoints that differ from our own. We gave col- leagues a chance to comment on these sections, and made a special effort to provide a balanced presentation while making our opinions clear. Readers will have to judge for themselves whether we succeeded.
Instructors wanted more guidelines and summary tables; these elements are shown in boxes throughout the book. The Practitioner Summaries and Researcher Agendas remain popular; they are updated. The references are expanded and freshened with many new sources, with classic papers stilI included. Because Preface ix some of the previously cited works were difficult to find, a much larger percent- age of the references now are widely available sources.
Figures, especially those showing screen designs, age quickl~ so many new user interfaces are shown. The printing in full color makes these figures even more valuable. Ways to UseThis Book We hope that practitioners and researchers who read this book will want to keep it on their shelves to consult when they are working on a new topic or seeking pointers to the literature. Instructors may choose to assign the full text in the order that we present it or to make selections from it.
The opening chapter is a good starting point for most students, but instructors may take different paths depending on their disci- plines. For example, instructors might emphasize the following chapters, listed by area: • Computer science: 2, 5, 6, 7,8, 9, 10, 14 • Psychology: 2, 4, 6,10,11,12,13,14 • Industrial engineering: 2, 4, 6, 10, 11, 12, 13, 14 • Library and information science: 2,4, 10, 12, 13, 14 • Business and information systems: 3, 4,6,10,11,12,14 • Education technology: 2,4,6,10, 13, 14 • Communication arts and media studies: 4, 6, 10, 12, 13 • Technical writing and graphic design: 3,4,6, 12, 13 Companion Web Site (www.com/DTUI) The presence of the World Wide Web has a profound effect on researchers, designers, educators, and students. We want to encourage intense use of the Web by all these groups and to integrate it into common practice. However, the volatility of the Web is not in harmony with the pennanence of printed books.
Publishing Web site URLs in the book would have been risky, because changes are made daily. For these and other reasons, we have established a Companion Web site to accompany this book. We hope that every reader will visit the site and send us ideas for improving it. x Preface Supplements A variety of supplemental materials for this text are available at the book's Com- panion Web site: www.
The following are accessible to all readers who register using the prepaid access card in the front of this book: • Links to hundreds of human-computer interaction resources, examples, and research that enhance and expand on the material in each chapter • Chapter/section summaries • Self-test questions and discussion questions for each chapter • Homework assignments and projects Acknowledgments Writing is a lonely process; revising is a social one. We are grateful to the many colleagues and students who contributed their suggestions. We appreciate the strong contributions from Jean-Daniel Fekete to Chapter 5 and Jennifer Preece to Chapter 10. Our close daily partners at the University of Maryland have had a great influence on our work: Ben Bederson, Allison Druin, Kent Norman, Anne Rose, and Fran<;ois Guimbretiere.