The UX Book Process and Guidelines for Ensuring a Quality User Experience

This book is destined to become a primary reference for just about anyone involved in the development of interactive products of almost any kind. It addresses both the design process and design principles and goes beyond traditional usability to address all aspects of the user experience. The authors have distilled two careers’ worth of research, practice and teaching into a concise,practicalandcomprehensiveguideforanyoneinvolvedindesigningfor the user experience of interactive products.—Deborah J. Mayhew, Deborah J. Mayhew Associates The UX Book covers the methods and guidelines for interaction design and evaluation that have been shown to be the most valuable to students and professionals. The students in my classes have been enthusiastic about the previous versions of this text that they used. This book will benefit anyone who wants to learn the right way to create high quality user experiences. Like good user interfaces, this text has been refined through multiple iterations and feedback with actual users (in this case, feedback from students and faculty who used earlier versions of the book in classes), and this is evident in the final result.— Brad A. Myers, Professor, HumanComputer Interaction Institute, School of Computer Science, Carnegie Mellon University The UX Book takes on a big challenge: a comprehensive overview of what it takes to design great user experiences. Hartson and Pyla combine theory with practicaltechniques: youleave thebook knowingnot just whatto do, butwhyit’s important.—Whitney Quesenbery, WQusability, author, Global UX: Design and research in a connected world

traditional usability to address all aspects of the user experience The authorshave distilled two careers’ worth of research, practice and teaching into aconcise, practical and comprehensive guide for anyone involved in designing forthe user experience of interactive products.—Deborah J Mayhew, Deborah J.Mayhew & Associates

The UX Book covers the methods and guidelines for interaction design andevaluation that have been shown to be the most valuable to students andprofessionals The students in my classes have been enthusiastic about theprevious versions of this text that they used This book will benefit anyone whowants to learn the right way to create high quality user experiences Like gooduser interfaces, this text has been refined through multiple iterations andfeedback with actual users (in this case, feedback from students and faculty whoused earlier versions of the book in classes), and this is evident in the finalresult.— Brad A Myers, Professor, Human-Computer Interaction Institute,School of Computer Science, Carnegie Mellon University

The UX Book takes on a big challenge: a comprehensive overview of what ittakes to design great user experiences Hartson and Pyla combine theory withpractical techniques: you leave the book knowing not just what to do, but why it’simportant.—Whitney Quesenbery, WQusability, author, Global UX: Design andresearch in a connected world

Process and Guidelines for Ensuring

a Quality User Experience

Process and Guidelines for Ensuring

a Quality User Experience

REX HARTSONPARDHA S PYLA

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Knowledge and best practice in this field are constantly changing As new research and

experience broaden our understanding, changes in research methods or professional practices, may become necessary Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information or methods described herein In using such information or methods they should be mindful of their own safety and the safety of others, including parties for whom they have a professional responsibility.

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1 Douglas Adams, The Hitchhiker’s Guide to the Galaxy

GOALS FOR THIS BOOK

Our main goal for this book is simple: to help readers learn how to create andrefine interaction designs that ensure a quality user experience (UX) A gooduser interface is like an electric light: when it works, nobody notices it (We used

to be able to use the telephone as a similar example, but now multifunctioncell phones with all kinds of modalities have thrown that example under thebus.) A good user interface seems obvious, but what is not obvious is how todesign it so that it facilitates a good user experience Thus, this book addressesboth what constitutes a positive user experience and the process by which itcan be ensured

Books need to be designed too, which means establishing user (reader)experience goals, requirements, user role (audience) definitions, and the like.Our goals for the reader experience include ensuring that:

n the book is easy to read

n the material is easy to learn

n the material is easy to apply

n the material is useful to students and practitioners

n the reader experience is at least a little bit fun

Our goals for the book content include:

n expanding the concept of traditional usability to a broader notion of user experience

n providing a hands-on, practical guide to best practices and established principles in a

n providing interaction design guidelines, including in-depth discussion of affordances and other foundational concepts

n facilitating an understanding of key interaction design creation and refinement activities, such as:

n contextual inquiry to understand user work that the design is to support

n contextual analysis to make sense of the raw contextual inquiry data

n requirements extraction

n design-informing modeling

n conceptual and detailed design

n establishing user experience goals, metrics, and targets

n building rapid prototypes

n performing formative user experience evaluation

n iterative interaction design refinement.

n describing alternative agile UX development methods

n providing pointers on how to get started with these ideas in your own work environment

Our goals for scope of coverage include:

n depth of understanding—detailed information about different aspects of the UX process (like having an expert accompanying the reader)

n breadth of understanding—as comprehensive as space permits

n range of application—the process and the design infrastructure and vocabulary, including guidelines, are not just for GUIs and the Web but for all kinds of interaction styles and devices, including ATMs, refrigerators, road signs, ubiquitous computing, embedded computing, and everyday things.

As we were wrapping up this book, the following quote from Liam Bannon(2011) came to our attention:

Some years ago, HCI researcher Panu Korhonen of Nokia outlined to me how HCI is changing, as follows: In the early days the Nokia HCI people were told “Please evaluate our user interface, and make it easy to use.” That gave way to “Please help us design this user interface so that it is easy to use.” That, in turn, led to a request: “Please help us find what the users really need so that we know how to design this user interface.” And now, the engineers are pleading with us: “Look at this area of life, and find us something interesting!” This, in a nutshell, tells a story of how HCI has moved from evaluation of interfaces through design of systems and into general sense-making of our world.

We were struck by this expressive statement of past, present, and future

directions of the field of HCI It was our goal in this book to embrace this scope

of historical roots, the changing perspectives of thought, and future design

directions

USABILITY IS STILL IMPORTANT

The study of usability, a key component of ensuring a quality user experience, is

still an essential part of the broad and multidisciplinary field of human–

computer interaction It is about getting our users past the technology and

focusing on getting things done for work In other words, it is about designing

the technology as an extension of human capabilities to accomplish something

and to be as transparent as possible in the process

A simple example can help boost this oft-unexplained imperative, “make it

transparent,” into more than a nice platitude Consider the simple task of

writing with pencil and paper The writer’s focus is all about capturing

expressions to convey content and meaning Much mental energy can be

directed toward organizing the thoughts and finding the right words to express

them No thought at all should be necessary toward the writing tools, the pencil

and paper, or computer-based word processor These tools are simply an

extension of the writer Until, that is, the occurrence of a breakdown, something

that causes an attention shift from the task to the tools

Perhaps the pencil lead breaks or a glitch occurs in the word processor

software The writer must turn attention away from the writing and think about

how to get the software to work, making the tool that was transparent to the

writer in the writing task become the focus of a breakdown recovery task

(Heidegger, 1962; Weller & Hartson, 1992) Similarly, interaction designs that

cause usability breakdowns for users turn attention away from the task to the

computer and the user interface

BUT USER EXPERIENCE IS MORE THAN USABILITY

As our discipline evolves and matures, more and more technology companies

are embracing the principles of usability engineering, investing in sophisticated

usability labs and personnel to “do usability.” As these efforts are becoming

effective at ensuring a certain level of usability in the products, leveling the field

on that front, new factors have emerged to distinguish the different competing

products

While usability is essential to making technology transparent, in these days

of extreme competition among different products and greater consumerawareness, that is not sufficient Thus, while usability engineering is still afoundation for what we do in this book, it does not stop there Because the focus

is still on designing for the human rather than focusing on technology, centered design” is still a good description We now use a new term to express aconcern beyond just usability: “user experience.”

“user-The concept of user experience conjures a broader image of what users comeaway with, inviting comparisons with theatre (Quesenbery, 2005), updating theold acronyms—for example, WYXIWYG, What You eXperience Is What You Get(Lee, Kim, & Billinghurst, 2005)—and spawning conferences—for example,DUX, Designing for User Experience We will see that, in addition to traditionalusability attributes, user experience entails social and cultural interaction,value-sensitive design, and emotional impact—how the interaction experienceincludes “joy of use,” fun, and aesthetics

A PRACTICAL APPROACH

This book takes a practical, applied, hands-on approach, based on theapplication of established and emerging practices, principles, and provenmethods to ensure a quality user experience The process is about practice,drawing on the creative concepts of design exploration and visioning to makedesigns that appeal to the emotions of users, while also drawing on engineeringconcepts of cost-effectiveness—making things as good as the resources permit,but not necessarily perfect

The heart of the book is an iterative and evaluation-centered UX lifecycletemplate, called the Wheel, for interaction design inPart I: Process Lifecycleactivities are supported by specific methods and techniques spelled out in

Chapters 3 through 19, illustrated with examples and exercises for you to applyyourself The process is complemented by a framework of principles andguidelines inPart II: Design Infrastructure and Guidelines for getting the rightcontent into the product And, throughout, we try to keep our eye on the prize,the pragmatics of making it all work in your development environment

ORDER OF THE MATERIAL

We faced the question of whether to present the process first or the designinfrastructure material We chose to start with the process because the processcontains development activities that should precede design We could just as

well have started with the design infrastructure chapters, especially the

interaction design guidelines, and you can read it in that order, too

One important reason for covering the process first is a practical

consideration in the classroom In our experience, we have found it effective to

teach process first so that students can get going immediately on their

semester-long team project Perhaps their designs might be a little better if

they had the guidelines first, but we find that it does not matter, as their projects

are about learning the process, not making the best designs Later, when we

do get into the design guidelines, the students appreciate it more because

they have a process structure for where it all goes

Use the Index

Use the index! We have tried to keep the text free of inter-section references So,

if you see a term you do not understand, use the index to find out where it is

defined and discussed

OUR AUDIENCE

This book is not a survey of human–computer interaction, usability, or user

experience Nor is it about human–computer interaction research It is a

how-to-do-it handbook, field guide, and textbook for students aspiring to be

practitioners and practitioners aspiring to be better The approach is practical,

not formal or theoretical Some references are made to the related science, but

they are usually to provide context to the practice and are not necessarily

elaborated

Anyone involved in, or wishing to learn more about, creating interaction

designs to ensure a quality user experience will benefit from this book It is

appropriate for a broad spectrum of readers, including all kinds ofpractitioners—

interaction designers, graphic designers, usability analysts, software engineers,

programmers, systems analysts, software quality-assurance specialists, human

factors engineers, cognitive psychologists, cosmic psychics, trainers, technical

writers, documentation specialists, marketing personnel, and project managers

Practitioners in any of these areas will find the hands-on approach of this book

to be valuable and can focus mainly on the how-to-do-it parts

Researchers in human–computer interaction will also find useful information

about the current state of user interaction design and guidelines in the field

Software engineers will find this book easy to read and apply because it relates

interaction design processes to those in software engineering

Academic readers include teachers or instructors and students Theperspectives of student and practitioner are very similar; both have the goal

of learning, only in slightly different settings and perhaps with differentmotivations and expectations

We have made a special effort to support teachers and instructors for use in acollege or university course at the undergraduate or graduate level We areespecially mindful that many of our teacher/instructor readers might be facedwith teaching this material for the first time or without much background oftheir own We have included, especially in the separate instructor’s guide, muchmaterial to help them get started

In addition to the material for course content, we have compiled a widerange of pedagogical and administrative support materials, for example, acomprehensive set of course notes, suggested course calendar, sample syllabi,project assignments, and even sample course Web pages The exercises areadapted easily for classroom use in an ongoing, semester-long set of in-classactivities to design, prototype, and evaluate an interaction design As instructorsgain the experience with the course, we expect they will tailor the materials, style,and content to the needs of their own particular setting

We also speak to our audiences in terms of their backgrounds and needs Wewant those working to develop large domain-complex systems in large-scaleprojects to have a sufficiently robust process for those jobs We also want toaddress young “UXers” who might think the full process is overly heavy andengineering-like We offer multiple avenues to lighter-weight processes Formany parts of the full process we offer abridged approaches

In addition, we have added a chapter on rapid evaluation techniques and achapter on agile UX methods, paralleling the agile software engineeringprocesses in the literature But we want these readers to understand that theabridged and agile processes they might use for product and small systemdevelopment are grounded in full and robust processes used to develop systemswith complex domains Even if one always takes the abridged or agile path, ithelps to appreciate the full process, to understand what is being abridged Also,

no matter what part of this book you need, you will find it valuable to see it set in

a larger context

Some readers will want to emphasize contextual inquiry, whereas others willwant to focus on design Although many of the process chapters have anengineering flavor, the design chapter takes on the more “designerly” essence ofdesign thinking, sketching, and ideation Others yet will want the heaviestcoverage on evaluation of all kinds, as that is the “payoff” activity We take the

approach that the broadest coverage will reach the needs of the broadest of

audiences Each reader can customize the way of reading the book, deciding

which parts are of interest and ignoring and skipping over any parts that are not

INCREASING MATURITY OF THE DISCIPLINE AND

AUDIENCE

We are approaching two decades since the first usability engineering process

books, such as Nielsen (1993), Hix and Hartson (1993), and Mayhew (1999),

and human–computer interaction as a discipline has since evolved and matured

considerably We have seen the World Wide Web mature to become a stock

medium of commerce The mobile communications revolution keeps users

connected to one another at all times New interaction techniques emerge and

become commonplace overnight to make the users’ information literally a

“touch” away

Despite all these technological advances, the need for a quality user

experience remains paramount If anything, the importance of ensuring a

positive user experience keeps increasing Given the pervasive information

overload, combined with the expectation that everyone is computer savvy, the

onus on designing for a quality user experience is even more critical these days

Among all these advances, many of the concepts of existing design and

development paradigms are more or less unchanged, but emerging new

paradigms are stretching our understanding and definition of our primary

mandate—to create an interaction design that will lead to a quality user

experience Approaches to accomplish this mandate have evolved from

engineering-oriented roots in the early 1990s to more design-driven

techniques today

Although much has been added to the literature about parts of the

interaction development process, the process is still unknown to many and

misunderstood by many and its value is unrecognized by many For example,

many still believe it is just about “usability testing.”

Since our first book (Hix & Hartson, 1993), we have conducted many short

courses and university courses on this material, working with literally hundreds

of students and user experience practitioners at dozens of locations in business,

industry, and government We have learned quite a bit more about what works

and what does not

It is clear that, in this same period of time, the level of sophistication among

our audiences has increased enormously At the beginning we always had to

assume that most people in our classes had no user experience background, hadnever heard of user experience specialists, and, in fact, needed some motivation

to believe in the value of user experience As time went on, we had to adjust theshort course to audiences that required no motivation and audiences

increasingly knowledgeable about the need for quality user experience and whatwas required to achieve it We started getting user experience specialists in theclass—self-taught and graduates of other user experience courses

WHAT WE DO NOT COVER

Although we have attempted a broad scope of topics, it is not possible to includeeverything in one book, nor is it wise to attempt it We apologize if your favorite topic

is excluded, but we had to draw the line somewhere Further, many of theseadditional topics are so broad in themselves that they cannot be covered adequately

in a section or chapter here; each could (and most do) fill a book of their own.Among the topics not included are:

n Accessibility and the American Disabilities Act (ADA)

n Internationalization and cultural differences

n Ergonomic health issues, such as repetitive stress injury

n Specific HCI application areas, such as societal challenges, healthcare systems, help systems, training, and designing for elders or other special user populations

n Special areas of interaction such as virtual environments or 3D interaction

Additionally, our extensive discussions of evaluation, such as usability testing,are focused on formative evaluation, evaluation used to iteratively improveinteraction designs Tutorials on performing summative evaluation (to assess alevel of performance with statistically significant results) are beyond our scope

ABOUT THE EXERCISES

The Exercises Are an Integral Part of the Course Structure

A Ticket Kiosk System is used as an ongoing user interaction developmentexample for the application of material in examples throughout the book Itprovides the “bones” upon which you, the reader or student, can build the flesh

of your own design for quality user experience In its use of hands-on exercisesbased on the Ticket Kiosk System, the book is somewhat like a workbook After

each main topic, you get to apply the new material immediately, learning the

practical techniques by active engagement in their application

Take Them in Order

As explained earlier, we could have interchanged Part I and Part II; either part

can be read first Beyond this option, the book is designed mainly for sequential

reading Each process chapter and each design infrastructure chapter build on

the previous ones and add a new piece to the overall puzzle Because the material

is cumulative, we want you to be comfortable with the material from one chapter

before proceeding to the next Similarly, each exercise builds on what you

learned and accomplished in the previous stages—just as in a real-world project

For some exercises, especially the one in which you build a rapid prototype,

you may want to spread the work over a couple of days rather than the couple of

hours indicated Obviously, the more time you spend working on the exercises,

the more you will understand and appreciate the techniques they are designed

to teach

Do the Exercises in a Group if You Can

Developing a good interaction design is almost always a collaborative effort, not

performed in a vacuum by a single individual Working through the exercises

with at least one other interested person will enhance your understanding and

learning of the materials greatly In fact, the exercises are written for small teams

because most of these activities involve multiple roles You will get the most out

of the exercises if you can work in a team of three to five people

The teamwork will help you understand the kinds of communication,

interaction, and negotiation that take place in creating and refining an

interaction design If you can season the experience by including a software

developer with responsibility for software architecture and implementation,

many new communication needs will become apparent

Students

If you are a student in a course, the best way to do the exercises is to do them in

teams, as in-class exercises The instructor can observe and comment on your

progress, and you can share your “lessons learned” with other teams

Practitioners: Get buy-in to do the exercises at work

If you are a practitioner or aspiring practitioner trying to learn this material in

the context of your regular work, the best way of all is an intensive short course

with team exercises and projects Alternatively, if you have a small interaction

design team in your work group, perhaps a team that expects to work together

on a real project, and your work environment allows, set aside some time (say,two hours every Friday afternoon) for the team exercises To justify the extraoverhead to pull this off, you will probably have to convince your projectmanager of the value added Depending on whether your manager is already UXliterate, your justification may have to start with a selling job for the value of aquality user experience (seeChapter 23)

Individuals

Do not let the lack of a team stop you from doing the exercises Try to find atleast one other person with whom you can work or, if necessary, get what you canfrom the exercises on your own Although it would be easy to let yourself skip theexercises, we urge you to do as much on each of them as your time permits

PROJECTS

Students

Beyond the exercises, more involved team projects are essential in a course ondevelopment for a quality user experience The course behind this book is, andalways has been, a learn-by-doing course—both as a university course and in all

of our short courses for business and industry

In addition to the small-scale, ongoing example application used by teams as aseries of in-class activities in conjunction with the book exercises, we cannotemphasize enough the importance of a substantial semester-long team projectoutside of class, using a real client from the community—a local company, store,

or organization that needs some kind of interactive software applicationdesigned The client stands to get some free consulting and even a systemprototype in exchange for serving as the project client

Instructors: See the instructor’s guide for many details on how to organizeand conduct these larger team projects The possibilities for project applicationsare boundless; we have had students develop interaction designs for all kinds ofapplications: electronic mail, an interactive Monopoly game, a personnelrecords system, interactive Yellow Pages, a process control system, a circuitdesign package, a bar-tending aid, an interactive shopping cart, a fast-foodordering system, and so on

those activities and may even already be doing some of them in your

development environment By making them part of a more complete and

informed development lifecycle, you can integrate what you know with new

concepts presented in the book

For example, many development teams use rapid prototyping Nonetheless,

many teams do not know how to make a low-fidelity prototype (as opposed to

one programmed on a computer) or do not know what to do with such a

prototype once they have one Many teams bring in users and have them try out

the interaction design, but teams often do not know what data are most

important to collect during user sessions and do not know the most effective

analyses to perform once they have collected those data Many do not know

about the most effective ways to use evaluation data to get the best design

improvements for the money And very few developers know about measurable

user experience targets—what they are, how to establish them, and how to use

them to help improve the user experience of an interaction design and to

manage the process We hope this book will help you answer such questions

ORIGINS OF THE BOOK

Real-World Experience

Although we have been researchers in human–computer interaction, we both

have been also teachers and practitioners who have successfully used the

techniques described in this book for real-world development projects, and we

know of dozens, if not hundreds, of organizations that are applying this material

successfully

One of us (RH) has been teaching this material for 30 years in both a

university setting and a short course delivered to hundreds of practitioners in

business, industry, government, and military organizations Obviously a much

broader audience can be reached by a book than can be taught in person, which

is why we have written this book Because this book is rooted in those courses, the

material has been evaluated iteratively and refined carefully through many

presentations over a large number of years

Research and Literature

In the Department of Computer Science at Virginia Tech, we (RH and

colleagues) established one of the pioneering research programs in

human–computer interaction back in 1979 Over the years, our work has had

the following two important themes

• Getting usability, and now UX, right in an interaction design requires an effective development process integrated within larger software and systems development processes.

• The whole point of work in this discipline, including research, is to serve effective practical application in the field.

The first point implies that human–computer interaction and designing foruser experience have strong connections to software and systems engineering.Difficulties arise if human–computer interaction is treated only as a psychology

or human factors problem or if it is treated as only a computer science problem.Many people who enter the HCI area from computer science do not bring to thejob an appreciation of human factors and the users Many people who work inhuman factors or cognitive psychology do not bring an appreciation forproblems and constraints of the software engineering world

The development of high-quality user interaction designs depends oncooperation between the roles of design and implementation The goals ofmuch of our work in the past decade have been to help (1) bridge the gapbetween the interaction design world and the software implementation worldand (2) forge the necessary connections between UX and software engineeringlifecycles

The second defining theme of our work over the past years has beentechnology exchange between academia and the real world—getting newconcepts out into the real world and bringing fresh ideas from the field of praxisback to the drawing boards of academia Ideas from the labs of academia are justcuriosities until they are put into practice, tested and refined in the face of realneeds, constraints, and limitations of a real-world working environment.Because this book is primarily for practitioners, however, it is not formal andacademic As a result, it contains fewer references to the literature than would aresearch-oriented book Nonetheless, essential references have been included;after all, practitioners like to read the literature, too The work of others isacknowledged through the references and in the acknowledgments

AROUSING THE DESIGN “STICKLER” IN YOU

We are passionate about user experience, and we hope this enthusiasm will takehold within you, too As an analogy,Eats, Shoots, & Leaves: The Zero ToleranceApproach to Punctuation by Lynn Truss (2003) is a delightful book entirely aboutpunctuation—imagine! If her book rings bells for you, it can arouse what she

calls your inner punctuation stickler You will become particular and demanding

about proper punctuation

With this book, we hope to arouse your inner design stickler We could think

of no happier outcome in our readers than to have examples of poor interaction

designs and correspondingly dreadful user experiences trigger in you a ghastly

private emotional response and a passionate desire to do something about it

This book is for those who design for users who interact with almost any kind

of device The book is especially dedicated to those in the field who get “hooked

on UX,” those who really care about the user experience, the user experience

“sticklers” who cannot enter an elevator without analyzing the design of the

controls

FURTHER INFORMATION ON OUR WEBSITE

Despite the large size of this book, we had more material than we could fit into

the chapters so we have posted a large number of blog entries about additional

but related topics, organized by chapter See this blog on our Website at

TheUXBook.com At this site you will also find additional readings for many of

the topics covered in the book

ABOUT THE AUTHORS

Rex Hartson is a pioneer researcher, teacher, and practitioner–consultant in

HCI and UX He is the founding faculty member of HCI (in 1979) in the

Department of Computer Science at Virginia Tech With Deborah Hix, he was

co-author of one of the first books to emphasize the usability engineering

process,Developing User Interfaces: Ensuring Usability Through Product & Process

Hartson has been principal investigator or co-PI at Virginia Tech on a large

number of research grants and has published many journal articles, conference

papers, and book chapters He has presented many tutorials, invited lectures,

workshops, seminars, and international talks He was editor or coeditor for

Advances in Human–Computer Interaction, Volumes 1–4, Ablex Publishing Co.,

Norwood, New Jersey His HCI practice is grounded in over 30 years of

consulting and user experience engineering training for dozens of clients in

business, industry, government, and the military

Pardha S Pyla is a Senior User Experience Specialist and Lead Interaction

Designer for Mobile Platforms at Bloomberg LP Before that he was a researcher

and a UX consultant As an adjunct faculty member in the Department of

Computer Science at Virginia Tech he worked on user experiencemethodologies and taught graduate and undergraduate courses in HCI andsoftware engineering He is a pioneering researcher in the area of bridging thegaps between software engineering and UX engineering lifecycle processes.

I (RH) must begin with a note of gratitude to my wife, Rieky Keeris, whoprovided me with a happy environment and encouragement while writing thisbook While not trained in user experience, she playfully engages a well-honednatural sense of design and usability with respect to such artifacts as elevators,kitchens, doors, airplanes, entertainment controls, and road signs that weencounter in our travels over the world You might find me in a lot of differentplaces but, if you want to find my heart, you have to look for whereverRieky is.

I (PP) owe a debt of gratitude to my parents and my brother for all theirlove and encouragement They put up with my long periods of absence fromfamily events and visits as I worked on this book I must also thank my brother,Hari, for being my best friend and a constant source of support as I worked onthis book

We are happy to express our appreciation to Debby Hix, for a careeer-longspan of collegial interaction We also acknowledge several other individuals withwhom we’ve had a long-term professional association and friendship at VirginiaTech, including Roger Ehrich, Bob and Bev Williges, Tonya Smith-Jackson, andWoodrow Winchester Similarly we are grateful for our collaboration andfriendship with these other people who are or were associated with theDepartment of Computer Science: Ed Fox, John Kelso, Sean Arthur, Mary BethRosson, and Joe Gabbard We are also grateful to Deborah Tatar and SteveHarrison of the Center for Human-Computer Interaction at Virginia Techfor steering us to consider more seriously the design thinking paradigm

of HCI

We are indebted to Brad Myers of Carnegie Mellon University for the use ofideas, words, examples, and figures in the contextual inquiry and modelingchapters Brad was instrumental in the evolution of the material in this bookthrough his patient adoption of and detailed feedback from early and

incomplete trial versions

In addition, we wish to thank Janet Davis of Grinnell College for her adoption

of an early draft of this book and for her detailed and insightful feedback

Thanks also to Jon Meads of Usability Architects, Inc for help with ideas forthe chapter on agile UX methods and to John Zimmerman of CMU forsuggesting alternative graphical representations of some of the models.Additionally, one paragraph ofChapter 4was approved by Fred Pelton.Susan Wyche helped with discussions and introduced us to Akshay Sharma, inthe Virginia Tech Department of Industrial Design Very special thanks toAkshay for giving us personal access to the operations of the Department ofIndustrial Design and to his approach to teaching ideation and sketching.Akshay also gave us access to photograph the ideation studio and workingenvironment there, including students at work and the sketches and prototypesthey produced And finally our thanks for the many photographs and sketchesprovided by Akshay to include as figures in design chapters.

It is with pleasure we acknowledge the positive influence of Jim Foley, DennisWixon, and Ben Shneiderman, with whom friendship goes back decades andtranscends professional relationships

We thank Whitney Quesenbery for discussions of key ideas andencouragement to keep writing Thanks also to George Casaday for manydiscussions over a long-term friendship We would like to acknowledge ElizabethBuie for a long and fruitful working relationship and for helpful discussionsabout various topics in the book And we must mention Bill Buxton, a friend andcolleague who was a major influence on the material about sketching andideation

We are grateful for the diligence and professionalism of the many, manyreviewers over the writing lifecycle, for amazingly valuable suggestions that havehelped make the book much better than what it started out to be Especially toTeri O’Connell and Deborah J Mayhew for going well beyond the call of duty indetailed manuscript reviews

We wish to thank the Department of Computer Science at Virginia Tech forall the support and encouragement

Among those former students especially appreciated for volunteering untoldhours of fruitful discussions are Terence Andre, Steve Belz, and Faith McCreary

I (RH) enjoyed my time working with you three and I appreciate what youcontributed to our discussions, studies, and insights

Susan Keenan, one of my (RH) first Ph.D students in HCI, was the onewho started the User Action Framework (UAF) work Jose (Charlie) Castilloand Linda van Rens are two special friends and former research

collaborators

We wish to thank all the HCI students, including Jon Howarth and MirandaCapra, we have had the pleasure of working with over the years Our discussions

about research and practice with Jon and Miranda have contributed

considerably to this book We extend our appreciation to Tejinder Judge for

her extensive help with studies exploring contextual inquiry and contextual

analysis

We also acknowledge all the students in classes where early drafts of this book

were tested for their feedback and suggestions

We also wish to acknowledge Mara Guimara˜es da Silva for very dedicated,

generous, and conscientious help in gathering and formatting the references in

this book

Special thanks to Colin David Campbell of Bloomberg L.P for the design of

the book cover and many diagrams in the book

Thanks to Mathilde Bekker and Wolmet Barendregt for discussions during

my (RH) visits to Technische Universiteit Eindhoven (TU/e) in the

Netherlands

Many thanks to Phil Gray and all the other nice people in the Department of

Computing Science at the University of Glasgow for hosting my (RH) wonderful

sabbatical in 1989 Special thanks to Steve Draper, Department of Psychology,

University of Glasgow, for providing a comfortable and congenial place to live

while I was there in 1989 And thanks to Dan Olson for good memories of doing

contextual studies on the Isle of Mull

And thanks to Jeri Baker, the director of the ONE Spirit organization

(www.nativeprogress.org), who has put up with my (RH) absence from my post

in helping her with that organization while working on this book

It is not possible to name everyone who has contributed to or influenced

our work, professionally or personally, and it is risky to try We have interacted

with a lot of people over the years whose inputs

have benefitted us in the writing If you feel that

we have missed an acknowledgement to you, we

apologize; please know that we appreciate you

nonetheless Our thanks go out to you anonymous

contributors

Finally, we thank the students for the fun we

have had with them at Usability Day parties and at

dinners and picnics at Hartveld In particular, we

thank Terence Andre for creating the UAF hat,

used at many meetings, and Miranda Capra for

baking a UAF cake for one of our famous Fourth

of July parties

Finally, we are grateful for all the support from Andre´ Cuello, Dave Bevans,Steve Elliot, and all the others at Morgan Kauffman It has been a pleasure towork with this organization.

Chapter 4: Contextual Analysis: Consolidating and Interpreting Work Activity Data 129

8.5 Design influencing user behavior 324

10.13 How UX targets help manage the user experience

Chapter 12: UX Evaluation Introduction 427

12.3 Types of formative and informal summative evaluation methods 432

14.5 Select and adapt evaluation method and data collection techniques 509

14.10 More about determining the right number of participants 529

15.7 Generating and collecting phenomenological evaluation data 550

Chapter 16: Rigorous Empirical Evaluation: Analysis 555

17.5 Formative reporting audience, needs, goals,

18.4 Parting thoughts: be flexible and avoid dogma during

Chapter 21: The Interaction Cycle and the User Action Framework 663

21.3 The user action framework—adding a structured knowledge

21.4 Interaction cycle and user action framework content categories 675

1Fine art and pizza delivery, what we do falls neatly in between.

– David Letterman

Objectives

After reading this chapter, you will:

1 Recognize the pervasiveness of computing in our lives

2 Be cognizant of the changing nature of computing and interaction and the need to

design for it

3 Understand the traditional concept of usability and its roots

4 Have a working definition of user experience, what it is and is not

5 Understand the components of user experience, especially emotional impact

6 Recognize the importance of articulating a business case for user experience

1.1 UBIQUITOUS INTERACTION

1.1.1 Desktops, Graphical User Interfaces, and the Web

Are Still Here and Growing

The “old-fashioned” desktop, laptop, and network-based computing systems are

alive and well and seem to be everywhere, an expanding presence in our lives

And domain-complex systems are still the bread and butter of many business,

industry, and government operations Most businesses are, sometimes

precariously, dependent on these well-established kinds of computing Web

addresses are commonplace in advertisements on television and in magazines

The foreseeable future is still full of tasks associated with “doing computing,” for

example, word processing, database management, storing and retrieving

information, spreadsheet management Although it is exciting to think about all

the new computing systems and interaction styles, we will need to use processes

for creating and refining basic computing applications and interaction styles for

years to come

1.1.2 The Changing Concept of Computing

That said, computing has now gone well beyond desktop and laptop computers,well beyond graphical user interfaces and the Web; computing has become farmore ubiquitous (Weiser, 1991) Computer systems are being worn by peopleand embedded within appliances, homes, offices, stereos and entertainmentsystems, vehicles, and roads Computation and interaction are also finding theirway into walls, furniture, and objects we carry (briefcases, purses, wallets, wristwatches, PDAs, cellphones) In the 2Wear project (Lalis, Karypidis, & Savidis,2005), mobile computing elements are combined in different ways by short-distance wireless communication so that system behavior and functionalityadapt to different user devices and different usage locations The eGadgetproject (Kameas & Mavrommati, 2005) similarly features self-reconfiguringartifacts, each with its own sensing, processing, and communication abilities.Sometimes, when these devices can be strapped on one’s wrist or in some wayattached to a person’s clothing, for example, embedded in a shoe, they arecalledwearable computers In a project at MIT, volunteer soldiers wereinstrumented with sensors that could be worn as part of their clothing, tomonitor heart rate, body temperature, and other parameters, to detect the onset

of hypothermia (Zieniewicz et al., 2002)

“Smart-its” (Gellersen, 2005) are embedded devices containingmicroprocessors, sensors, actuators, and wireless communication to offeradditional functionality to everyday physical world artifacts that we all “interact”with as we use them in familiar human activities A simple example is a set of carkeys that help us track them so we can find them if they are lost

Another example of embedding computing artifacts involves uniquelytagging everyday objects such as milk and groceries using inexpensive machine-readable identifiers It is then possible to detect changes in those artifactsautomatically For example, using this technology it is possible to remotely poll arefrigerator using a mobile phone to determine what items need to be picked upfrom the grocery store on the way home (Ye & Qiu, 2003) In a project at MITthat is exactly what happened, or at least was envisioned: shoes were

instrumented so that, as the wearer gets the milk out for breakfast in themorning, sensors note that the milk is getting low Approaching the grocerystore on the way home, the system speaks via a tiny earphone, reminding of theneed to pick up some milk (Schmandt, 1995)

Most of the user–computer interaction attendant to this ubiquitous computing

in everyday contexts is taking place without keyboards, mice, or monitors AsCooper (2004) says, you do not need a traditional user interface to have interaction.Practical applications in business already reveal the almost unlimitedpotential for commercial application Gershman and Fano (2005) cite an

example of a smart railcar that can keep track of and report on its own location,

state of repair, whether it is loaded or empty, and its routing, billing, and security

status (including aspects affecting homeland security) Imagine the promise this

shows for improved efficiency and cost savings over the mostly manual and

error-prone methods currently used to keep track of railroad cars

Proof-of-concept applications in research labs are making possible what was

science fiction only a few years ago Work at the MIT Media Lab (Paradiso, 2005),

based on the earlier “Smart Matter” initiative at Xerox PARC, employs sensate

media (Paradiso, Lifton, & Broxton, 2004) arranged as surfaces tiled with dense

sensor networks, in the manner of biological skin, containing multimodal

receptors and sensors The goal is to use this kind of embedded and distributed

computing to emulate living, sensitive tissue in applications such as robotics,

telemedicine, and prosthetics Their Tribble (Tactile Reactive Interface Built By

Linked Elements) is an interesting testbed using a spherical structure of these

nodes that can sense pressure, temperature, sound, illumination, and tactile

stimulations and can respond with sound, vibration, and light

More and more applications that were in research labs are now moving into

commercial adoption For example, robots in more specialized applications

than just housecleaning or babysitting are gaining in numbers (Scholtz, 2005)

There are robotic applications for healthcare rehabilitation, including systems

to encourage severely disabled children to interact with their environment

(Lathan, Brisben, & Safos, 2005), robotic products to assist the elderly (Forlizzi,

2005), robots as laboratory hosts and museum docents (Sidner & Lee, 2005),

robot devices for urban search and rescue (Murphy, 2005), and, of course,

robotic rover vehicles for unmanned space missions (Hamner et al., 2005)

1.1.3 The Changing Concept of Interaction

Sitting in front of a desktop or laptop usually conveys a feeling of “doing

computing” to users Users are aware of interacting with a computer and

interaction is purposeful: for exchanging information, for getting work done,

for learning, for play or entertainment, or just for exploring

When we drive a car we are using the car’s built-in computer and maybe even a

GPS, but we do not think of ourselves as “doing computing.” Tscheligi (2005)

paraphrases Mark Weiser: “the world is not a desktop.” Perhaps the most notable

and most recognizable (by the public) example of interaction away from the

desktop is seen in mobile communications With an obviously enormous market

potential, mobile communications are perhaps the fastest growing area of

ubiquitous computing with personal devices and also represent one of the most

intense areas of designing for a quality user experience (Clubb, 2007; Kangas &

Kinnunen, 2005; Macdonald, 2004; Venkatesh, Ramesh, & Massey, 2003)

3D Applications

Doug A Bowman, Department of Computer Science, Virginia Tech

Motion controls Freehand gestures “Natural” user interfaces They go by many names, but interfaces involvingphysical interaction in 3D space are cropping up everywhere these days Instead of pressing buttons or pushing onjoysticks, gamers are swinging their arms, jumping up and down, or leaning their whole bodies to play in 3D virtualworlds Instead of using a remote control, people are making mid-air gestures to control the components of their hometheaters Instead of looking for restaurants on a 2D map, mobile phone users look at augmented views of the realworld through their phone’s cameras All this 3D interaction is certainly very cool, but does it necessarily makeinterfaces more “natural” or usable? How should we design 3D interaction to ensure a quality user experience?Three-dimensional user interfaces (3D UIs) are very much an open field of research; there is much we do not yetknow What I am going to review here are a few of the major things we have learned over the last couple of decades

of research in this area For a comprehensive introduction to the field of 3D UIs, see the book 3D User Interfaces:Theory and Practice (Addison-Wesley, 2005)

As you might expect, 3D UIs that replicate an action that people do in the real world can be very successful Wecall these “natural” or “high-fidelity” 3D UIs For example, using physical turning and walking movements(measured by a position tracking system) to change your view of the virtual world is easy to comprehend and results

in high levels of spatial understanding Swinging your arms to make your character swing a virtual golf club is funand engaging, requiring no special expertise But natural 3D interaction has its limitations, as well It can be difficult

to reproduce exactly the action people use in the real world, resulting in misunderstanding An experienced golfermight expect a slight twitch of the wrists at impact to cause the ball to draw from right to left, but it is unlikely thatthe interface designer included this in the technique In fact, if an extremely realistic golf swing technique weredeveloped, it probably would not be very fun for most players—I personally would only hit the ball 50 yards much

of the time!

Another limitation of natural 3D interaction is that the user is constrained to things they can do in the real world.This leads to our second guideline, which is that “magic” 3D interaction can allow users to perform many tasks morequickly and effectively It is a virtual world, after all, so why restrict ourselves to only real-world abilities? Magictechniques can be used to enhance our physical abilities (e.g., a person can pick up a 10-story building and place itsomewhere else in the virtual city), our perceptual abilities (e.g., we can give the user “X-ray vision” like Superman soshe can see what is on the other side of the wall), and even our cognitive abilities (e.g., the system can provideinstructions to users to help them navigate through a complicated 3D world)

While we do not want to constrain the user’s abilities in a 3D UI, we do want to provide constraints that helpthe user to interact more easily and effectively For example, in an application for interior designers, even though

we could allow users to place furniture anywhere in 3D space, it only makes sense to have furniture sitting upright

on the floor Therefore, 3D manipulation techniques in this case should only allow the user to control three

parameters: 2D position on the floor and rotation around the vertical axis Many 3D input devices are inherently

such as the Sensable Phantom).

If appropriate constraints are not provided, users not only become less precise, they may also become fatigued(imagine how tired your arm would feel if you tried to sketch 3D shapes in mid-air for 15 minutes) So the lastguideline I want to highlight is to design for user comfort In many computer interfaces, physical comfort is not a majorissue, but 3D interaction usually involves large-scale physical movements and the use of many parts of the body (notjust the hand and fingers) What is more, 3D UIs for virtual reality often involve big, surrounding 3D displays that canmake users feel dizzy or even nauseated As a result, 3D UI designers have to take special care to design interfacesthat keep users feeling as comfortable as possible For example, manipulation techniques should allow users tointeract with their arms propped against their bodies or a physical surface 3D UIs should avoid rapid movementsthrough the virtual world or unnatural rotations of the view that can make people feel sick And if stereoscopicdisplays are used, keeping virtual objects at a comfortable distance can help avoid eye strain

Well-designed 3D UIs can make for an engaging, enjoyable, and productive user experience Knowing thefoundational principles of human–computer interaction and UX design is a great start, but using 3D-specific resultsand guidelines such as these will help ensure that your 3D interaction is a success

As an aside, it is interesting that even the way these devices are presented

to the public reveals underlying attitudes and perspectives with respect to

user-centeredness For example, among the synonyms for the device,

“cellphone” refers to their current implementation technology, while “mobile

phone” refers to a user capability

Interaction, however, is doing more than just reappearing in different devices

such as we see in Web access via mobile phone Weiser (1991) said “ the most

profound technologies are those that disappear.” Russell, Streitz, and Winograd

(2005) also talk about the disappearing computer—not computers that are

departing or ceasing to exist, but disappearing in the sense of becoming

unobtrusive and unremarkable They use the example of electric motors, which

are part of many machines we use daily, yet we almost never think about electric

motors per se They talk about “making computers disappear into the walls and

interstices of our living and working spaces.”

When this happens, it is sometimes called “ambient intelligence,” the goal of

considerable research and development aimed at the home living environment

In the HomeLab of Philips Research in the Netherlands (Markopoulos et al.,

2005), researchers believe “that ambient intelligence technology will mediate,

User Experience

User experience is the totality of the effect or effects felt by a user as a result of interaction with, and the usage context of,

a system, device, or product, including the influence of usability, usefulness, and emotional impact during interaction, and savoring the memory after interaction.

"Interaction with" is broad and embraces seeing, touching, and thinking about the system

or product, including admiring it and its presentation before any physical interaction.