DESIGNING THE USER INTERFACE docx

DESIGNING THE USER INTERFACE
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DESIGNING THE USER INTERFACE
DESIGNING THE USER INTERFACE
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Library
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Shneiderman,
Ben.
Designing the user interface: strategies for effective human-computer interaction / Ben
Shneiderman, Catherine Plaisant 4th ed.
p.cm.
Includes bibliographical references and index.
ISBN 0-321-19786-0
1.
Human-computerinteraction.
2.
User interfaces (Computer systems) I. Plaisant,
Catherine.
II.
Title.
QA76.9.H85S542004
005.1 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 orbyany 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 ofthis 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 alluringscenarios 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
interactionis 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
otherdisciplines. 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 chapteron the World Wide Web
and
instead describe Web-based, desktop,
and
mobile device designs throughout.
Every chapteris 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 chapteris moved forward in thebook. Part
IV
emphasizes Quality
ofService
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
showninboxes throughoutthebook. ThePractitionerSummaries
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
userinterfaces 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 pointfor
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.aw-bc.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.aw-bc.com/DTUI. 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 Chapter5
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.
We
give special thanks to Charles Kreitzberg
and
Gary Marchionini for their personal
and
professional
support
over
many
years.
Extensive comments from the review panel played a strong role
in
our
revi-
sions. These individuals made numerous constructive suggestions:
Robert St. Amant,
North
Carolina
State
University
Catherine
I.

Beaton,
Rochester
Institute of
Technology
Richard
F.
Bellaver,
Ball
State
University
William
H.
Bowers,
Penn
State
Berks-Lehigh
Valley
College
Roger
J.
Chapman,
Ohio
State
University
AndrewJohnson,
University
of
Illinois
at
Chicago

Bill
Killam,
User-Centered
Design,
Inc.
Alfred Kobsa,
University
of
California,
Irvine
Adrienne Olnick Kutzschan,
Queen's
University,
Canada
Bruce
R.
Maxim,
University
of
Michigan-Dearborn
D.
Scott McCrickard,
Virginia
Tech
Jane Webster,
Queen's
University,
Canada
Preface
xi

In addition, colleagues commented generously
on
certain
chapters
or
sections
for which they
were
especially knowledgeable: Len Bass,
Stephen
Brewster, Jus-
tine
Casselt
Andy
Cockburn,
Mary
Czerwinski, Daniel DeMenthon, Mikael
Fernstrom, Evan Golub, ArtGraesser, Michael Green,
Harry
Hochheiser, Bonnie
John, Lewis Johnson, Dan Olsen,
Judy
Olson,
Ian
Pitt, Theresa-Marie Rhyne,
George Robertson, Bernhard Suhm,Alistair Sutcliffe,
and
Colin Ware. We
appre-
ciate Kendra Knudtzon's help

with
the figures,
and
the
many
people
and
orga-
nizations that provided figures are acknowledged at the
end
of
the
book. Roger
Chapman and
Adam
Perer played
instrumental
roles
in
the
development
of
much of the material on the book's
Companion
Web site.
The publisher's editorial
and
production
staff was actively
involved

in
this
book from the start.
We
appreciate the contributions of Michael Hirsch, Maite
Suarez-Rivas, Joyce Wells, Jennifer Pelland, Jeffrey Holcomb, Lesly
Hershman,
Meghan James,
and
others. The copy editor, Rachel Wheeler,
taught
us
a lot
about lucid
and
informative writing.
We
apologize
if
we
have
left
out
anyone.
We
also appreciate the
students
and
professionals from
around

the
world
who
sentcomments
and
suggestions. Their provocative questions about
our
growing
discipline and profession encourage us daily.
Ben Shneiderman ()
Catherine Plaisant ()

Brief Contents
Preface
vii
Part I
Chapter 1
Chapter 2
Part
II
Chapter 3
Chapter 4
Chapter 5
Part III
Chapter 6
Chapter 7
Chapter 8
Chapter 9
Chapter
10

Part
IV
Chapter
11
Chapter
12
Chapter 13
Chapter 14
Introduction 1
Usability
of
Interactive
Systems
3
Guidelines, Principles,
andTheories
59
Development Processes 107
Managing
Design Processes 109
Evaluating Interface Designs 139
SoftwareTools 173
Interaction Styles
211
Direct
Manipulation
and Virtual
Environments
213
Menu

Selection, Form Fillin, and Dialog Boxes 267
Command
and Natural
Languages
315
Interaction Devices 345
Collaboration 409
Design Issues
451
Quality
of
Service 453
Balancing Function and Fashion 477
User Manuals,
Online
Help,
andTutorials
521
Information
Search and Visualization 559
Afterword
Societal and
Individual
Impact
of
User Interfaces 609
Name
Index 623
Subject Index 635
Acknowledgments

649
About
the
Authors
653
xiii

Part I
Chapter 1
Chapter 2
Part II
Chapter 3
Chapter 4
Contents
Introduction
Usability
of
Interactive
Systems
3
1.1
Introduction
4
1.2
Usability
Requirements 12
1.3
Usability
Measures
15

1.4
Usability
Motivations
17
1.5
Universal
Usability
24
1.6
Goals
for
Our
Profession 39
Practitioner's
Summary
44
Researcher's
Agenda
44
Guidelines, Principles, and
Theories
59
2.1
Introduction
60
2.2 Guidelines
61
2.3 Principles
66
2.4 Theories 82

2.5 Object-Action Interface
Model
95
Practitioner's
Summary
101
Researcher's Agenda 102
Development Processes 107
Managing
Design Processes 109
3.1
Introduction
110
3.2 Organizational Design
to
Support
Usability
111
3.3 TheThree Pillars
of
Design
114
3.4
Development
Methodologies
118
3.5 Ethnographic
Observation
122
3.6 Participatory Design 125

3.7 Scenario
Development
127
3.8 Social
Impact
Statement
for
Early Design Review 129
3.9 Legallssues
131
Practitioner's
Summary
133
Researcher's
Agenda
134
Evaluating Interface Designs 139
4.1
Introduction
140
4.2
Expert Reviews
141
4.3 UsabilityTesting
and
Laboratories
144
4.4 Survey
Instruments
150

xv
xvi Contents
Chapter 5
4.5 AcceptanceTests
162
4.6 Evaluation During
Active
Use 163
4.7 Controlled Psychologically Oriented Experiments 167
Practitioner's
Summary
169
Researcher's Agenda 169
SoftwareTools 173
5.1
Introduction
174
5.2
Specification
Methods
175
5.3
Interface-BuildingTools 183
5.4 Evaluation and CritiquingTools 203
Practitioner's
Summary
205
Researcher's Agenda 206
Part III
Chapter 6

Interaction Styles
211
Direct Manipulation and Virtual
Environments
213
6.1
Introduction 214
6.2
Examples
of
Direct
Manipulation
215
6.3 Discussion
of
Direct
Manipulation
231
6.4 3D Interfaces
241
6.5 Teleoperation 246
6.6 Virtual and Augmented Reality 249
Practitioner's
Summary
258
Researcher's Agenda 258
Chapter 7 Menu Selection, Form Fillin, and Dialog Boxes 267
7.1
Introduction 268
7.2

Task-Related Menu Organization 269
7.3
Single Menus 270
7.4
Combinations
of
Multiple
Menus
280
7.5
Content Organization 286
7.6
Fast
MovementThrough
Menus
294
7.7
Data Entry
with
Menus: Form Fillin, Dialog Boxes,
and Alternatives 295
7.8
Audio Menus and
Menus
for
Small Displays 304
Practitioner's
Summary
309
Researcher's Agenda 309

Chapter 8 Command and Natural Languages 315
8.1
Introduction 316
8.2 Functionality
to
Support
Users'Tasks
319
8.3
Command-Organization Strategies
321
8.4 The Benefits
of
Structure 325
8.5 Naming and Abbreviations 328
8.6 Natural Language in
Computing
331
Practitioner's
Summary
340
Researcher's Agenda
341
Chapter 9 Interaction Devices 345
9.1
Introduction 346
9.2 Keyboards and Keypads 348
9.3 Pointing Devices 358
9.4 Speech and
Auditory

Interfaces 374
9.5
Displays-Small
and Large 385
9.6 Printers 397
Practitioner's
Summary
399
Researcher's Agenda 400
Chapter 10 Collaboration 409
10.1
Introduction 410
10.2 Goals
of
Collaboration 412
10.3 Asynchronous Distributed Interfaces:
Different Time, Different Place 416
10.4 Synchronous Distributed Interfaces: Different Place,
Same
Time
429
10.5 Face-to-Face Interfaces: Same Place, Same
Time
437
Practitioner's
Summary
445
Researcher's Agenda 445
Part
IV

Design Issues
451
Chapter
11
Quality
of
Service 453
11.1
Introduction 454
11.2
Models
of
Response-Time Impacts 455
11.3
Expectations and
Attitudes
462
11.4
User
Productivity
466
11.5
Variability in Response
Time
468
11.6
Frustrating Experiences 470
Practitioner's
Summary
472

Researcher's Agenda 474
Chapter 12 Balancing Function
and
Fashion 477
12.1
Introduction 478
12.2 Error Messages 479
12.3
Nonanthropomorphic
Design 484
12.4 Display Design 490
12.5
Window
Design
501
12.6 Color
510
Practitioner's
Summary
514
Researcher's Agenda 515
Chapter 13
User
Manuals,
Online
Help,
and
Tutorials
521
13.1

Introduction 522
13.2 Paper Versus Online
Manuals
525
13.3 Reading
from
PaperVersus
from
Displays 529
13.4 Shaping the Content
of
the
Manuals
531
13.5 Online
Manuals
and Help 539
Contents
xvii
xviii
Contents
13.6 OnlineTutorials, Demonstrations, and Guides 546
13.7 Online
Communities
for
User Assistance
551
13.8 The Development Process 553
Practitioner's
Summary

554
Researcher's Agenda 554
Chapter 14 Information Search and Visualization 559
14.1
Introduction
560
14.2 Search inTextual Documents and Database Querying 563
14.3
Multimedia
Document
Searches 570
14.4 Advanced Filtering and Search Interfaces
574
14.5 InformationVisualization 580
Practitioner's
Summary
601
Researcher's Agenda 602
Afterword
Societal and Individual Impact
of
User Interfaces 609
Name Index 623
Subject Index 635
Acknowledgments 649
About
the
Authors
653
PART

Introduction
chapter
Usability
of
Interactive
Systems
Designing
an
object
to
be
simple
and
clear takes
at
least
twice
as
long
as
the usual way. It requires concentration
at
the outset on
how
a clear
and
simple system would work,
followed by the steps required
to

make
it
come out that
way-steps
which are often much harder
and
more complex
than the ordinary ones. It also requires relentless pursuit of
that simplicity even
when
obstacles appear which would
seem
to
stand
in
the way of that simplicity.
T.
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The
Home
Computer
Revolution,
1977
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1 · 1 Introduction
New technologies provide
extraordinary-almost
supernatural-powers
to
those people who master them. Networked computerswith advanced interfaces
are compelling
new
technologies that are being rapidly disseminated. Great

excitement spreads as designers provide remarkable functions
in
carefully
crafted interactive devices and interfaces. The opportunities for rule-breaking
innovators and business-focused entrepreneurs are substantial,
and
the impacts
on individuals, organizations, and cultures are profound.
Like early photography equipment or automobiles, early computers
were
usable only by people who devoted effort to mastering the technology. Harness-
ing the computer's power is a task for designers
who
combine
an
understand-
ing of technology with a sensitivity to
human
capacities
and
needs.
Human
performance and user experience with computer
and
information
systems will remain a rapidly expanding research
and
development topic
in
the

corning decades. The interdisciplinary design science of human-computer
interac-
tion
began by combining the data-gathering
methods
and
intellectual frame-
work of experimental psychology with the powerful
and
widely
used
tools
developed from computer science. Then, contributions accrued from educational
and
industrial psychologists, instructional
and
graphic designers, technical
writers, experts in human factors or ergonomics, information architects,
and
adventuresome anthropologists and sociologists.
And
now, as computers
and
user interfaces are becoming the basis for increasingly powerful sociotechnical
systems, policy analysts, economists, lawyers, privacy advocates, and ethicists
are playing a growing role.
1.1 Introduction 5
User interfaces help
produce
business

success stories
and
Wall
Street
sensa-
tions. They also
produce
intense
competition,
copyright-infringement
suits,
intellectual-property battles,
mega-mergers,
and
international
partnerships.
Crusading
Internet visionaries
promote
a
world
with
free access
to
music,
while equally
devoted
protectors of creative artists
argue
for

fair
payments.
User interfaces are also
controversial
because
of
their
central
role
in
national identification schemes,
homeland
defense,
crime
fighting,
medical
records management,
and
so on. In
the
aftermath
of
the
September
11, 2001
terrorist attacks,
some
members
of
the

U.s.
Congress
blamed
the
inadequacies
of
user
interfaces for the failure to detect
the
terrorists.
At
an
individual
level,
user
interfaces
change
many
people's
lives: effec-
tive
user
interfaces for professionals
mean
that
doctors
can
make
more
accu-

rate
diagnoses
and
pilots can fly
airplanes
more
safely;
at
the
same
time,
children
can
learn
more
effectively
and
graphic
artists
can
explore
creative
possibilities
more
fluidly.
Some
changes,
however,
are
disruptive.

Too
often,
users
must
cope
with
frustration,
fear,
and
failure
when
they
encounter
excessively complex
menus,
incomprehensible
terminology,
or
chaotic
navi-
gation
paths.
What
user
wouldn't
be
disturbed
by
receiving
a

message
such
as "Illegal
Memory
Exception: Severe
Failure"
with
no
guidance
about
what
to
do
next?
The steadily growing interest
in
user-interface design,
which
spans
remark-
ably diverse communities, stems from a
desire
to
improve
the
user
experience
(Figs.
1.1
to 1.3

show
some
popular
operating
systems). In
business
settings,
better decision-support
and
desktop-publishing
tools
support
entrepreneurs,
while
in
home
settings digital
photos
and
voice
messaging
enhance
family
rela-
tionships. A significant
number
of
people
take
advantage

of
the
World
Wide
Web's remarkable educational
and
cultural
heritage
resources,
e-government
services,
and
health-support
communities.
Access to
outstanding
art
objects
from China, music from Indonesia,
sports
from Brazil,
and
entertainment
from Hollywood enriches daily life for
many
users,
including
those
with
dis-

abilities
and
limited literacy (Figs. 1.4
to
1.6
show
examples
of
popular
web
sites). Globalization promoters
and
dissenters
debate
the
role
of
technology
for
international development.
Making these diverse applications successful requires contributions from
researchers
and
practitioners
in
many
fields. Academic
and
industrial researchers
are developing descriptive taxonomies,

explanatory
theories, predictive
models,
and
prescriptive guidance, while
experimenters
are collecting empirical
data
as
a basis for
new
theories. The motor, perceptual,
and
cognitive
foundations
are
growing firmer, while the social, economic,
and
ethical
impacts
are
becoming
clearer. Designers are using
sound
(such
as
music
and
voice), three-dimensional
representations, animation,

and
video
to
improve
the
appeal
and
information
content of interfaces. Techniques
such
as
direct
manipulation,
telepresence,
and
6
Chapter
1 Usability
of
Interactive Systems
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Figure 1.1
Mac as X. All
windows
are set
to
a
"metallic"

theme.The top-left
window
shows
eBay (). a popular online auction site.The
top-right
window
shows
an
Xterm
window,
which gives users direct access into the
Unix
underpin-
nings
of
Mac as X. ITunes, the built-in music player
for
Mac, is
shown
on the
bottom
left.The
bottom-right
program is iCal, the built-in calendar program.The bottom
of
the screen also
shows
the Dock, the menu
of
frequently

accessed items
where
selected
items
grow
larger on mouse-over.
virtual reality
may
change the
ways
that
we
interact with technology,
think
about
our
work, or relate to
our
friends.
Sociologists, anthropologists, policymakers,
and
managers are currently
dealing
with
issues of organizational impact, computer anxiety, job redesign,
distributed teamwork, work-at-home schemes,
and
long-term societal changes.
As face-to-face interaction gives
way

to screen-to-screen, does organizational
loyalty
and
personal trust dissipate?
Designers face the challenge of providing services on small-, wall-,
and
mall-
sized displays, ranging from portable devices
such
as cell
phones
or
pocket
1.1
Introduction
7
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Figure
1.2
Linux RedHat 8
with
KDE
3
window
manager.
The
top-left
window
is GNU Emacs,
an
editing
environment
popular
for
programming.
At
the
bottom

left
is a
terminal
window
which
provides
a
simple
command-line
interface
for
the
user. The
top-right
window
isThe
GIMP,
a graphical
image
manipulation
program;
below
this
is
the
Mozilla browser,
displaying
Slashdot.org, a
popular
news

web
site.
At
the
very
bot-
tom
is
XMMS,
for
playing music.The
taskbar
at
the
bottom
controls
multiple
desk-
tops.
All
these programs,
including
the
operating
system, are free and open source.
computers to large plasma panels
and
projected displays. The plasticity of their
designs
must

ensure smooth conversion across display-size variations, delivery
by
way
of web browsers
or
the telephone, translation into multiple languages,
and compatibility with accessibility-support devices for disabled users.
Some innovators promise
that
desktop computers
and
their user interfaces
will disappear, only to become ubiquitous, pervasive, invisible,
and
embedded
in the
surrounding
environment. They believe that novel appliances will be