Silicon Graphics IRIS InSight®:
An SGML Success Story
Robert J. Glushko, Passage Systems, Inc.
Ken Kershner, Silicon Graphics, Inc.
Technical Communication, 40(3), 1993, 394-402.
This paper tells the story of Silicon Graphics IRIS InSight,
the first system for viewing online documentation from a computer
vendor that uses SGML, the Standard Generalized Markup Language
(ISO 8879) . SGML's explicit encoding of structure and its
separation of structure and presentation make possible structure-
based search, alternative structural views of the same
information, dynamic reformatting, and alternative presentation
styles. SGML enables Silicon Graphics to produce more consistent
and complete documents while automating many otherwise tedious
production tasks. Over time SGML will enable Silicon Graphics to
reuse much more of the information it creates and better
synchronize the development of documentation with the products it
Since late 1992 the IRIS InSight viewer and the core IRIS
InSight Document Library, which contains several technical
manuals, have been bundled free with every Silicon Graphics
computer. (IRIS InSight is a family of support tools that provide
online access to product, support and technical information, and
various services). This bundling makes online documentation
pervasive and truly cost-effective. The ubiquity of the online
documentation viewer and the openness of an SGML based-system
allows developers of Silicon Graphics software applications or
other Silicon Graphics customers to use IRIS InSight to deliver
online documentation for their own applications. Usability tests
with IRIS InSight demonstrate that a clear majority of first-time
users prefer it to using hardcopy manuals.
We begin this paper with the user's perspective on IRIS
InSight. While SGML is the basis of many of the viewer's
functions, SGML is not directly visible to end users. SGML is
visible and important to varying degrees to authors, production
staff, management, and others involved in the overall IRIS
InSight effort. We explain these different perspectives so that
others can appreciate how the costs and benefits of SGML are
allocated among different individuals and organizations in an
overall SGML-based publishing process.
Since the IRIS InSight effort began in late 1990, we've seen
an enormous increase in the visibility and viability of SGML.
The growing success of SGML makes our decision to adopt SGML in
IRIS InSight seem far more obvious and easy than it was at the
time. We review the key decisions and turning points in the
project's history to identify important lessons for others
considering a similar project.
The first author has worked as a consultant to Silicon
Graphics from the beginning of its online documentation effort
and his company, Passage Systems, continues to support Silicon
Graphics and its developers by providing training, document
conversion services, and document management software for IRIS
InSight and SGML-based publishing. The second author has managed
the IRIS InSight project since its inception and for a time
concurrently managed a technical writing group at Silicon
IRIS InSight is an information viewer that takes advantage
of the rich visual processing capabilities of Silicon Graphics
computers while providing all the familiar entry points into a
book. Figure 1 is a "screen shot" showing a typical user
interaction with the system. Many of the low-level features of
IRIS InSight reflect its conformance to the user interface
standards embodied in the Motif toolkit and the X Window System.
The top pane in Figure 1 shows the IRIS InSight document
library, in which books for different types of users or
applications are arranged on named bookshelves. A user can
directly view an online book by double-clicking its icon or
title. Alternatively, the user can search for information in one
or more selected books by single-clicking them and then typing
the search terms or phrases into the search field (in the middle
of the screen shot in Figure 1). Boolean and proximity operators
can be used to refine a search. The sections of books in which
the search terms can be found are displayed in a "hit list" the
lower pane of Figure 1.
The display of a selected book or book section appears as in
Figure 2. The display is organized as a "structure view" in the
top pane and a "content view" below it. In Figure 2, the
structure view in the top pane is the book's table of contents,
presented as a dynamic outline for progressive display of details
,, but other structure views like lists of tables, figures,
or code examples are also available. Searches can be restricted
to a particular kind of content element for more precision; for
example, a user can search only in titles, figure captions, or
code examples. The content and structure views are synchronized
so that a user can quickly navigate to any part of the book by
double-clicking on an item in a structure view.
The user's current position in the book is indicated by
highlighting a title in the structure view. Numbers in front of
each title indicate the number of matches to the current search
expression (indicated in the within-book search field at the
bottom of the window in Figure 2). This structured search
feedback technique, first used by SuperBook , has been shown
to enhance search and navigation in online publications .
In the content view in the bottom pane of Figure 2, the text
of the book appears in a scrolling window. This display is NOT
page-based; the window can be arbitrarily resized, and the text
is wrapped and reformatted as needed. Selectable "See" and "See
also" cross references to another section or book (hypertext
links) are marked on the screen by presenting them in a
distinctive color. Links within a book instantly scroll the
content and structure views within the same window, while links
to another book open a new window. Glossary terms, marked by
underlining, open a window containing their definitions when they
IRIS InSight books can contain in-line or link to graphics,
audio, video, animation, and other digital media elements for
which Silicon Graphics computers are exceptionally well-suited. A
sample screen display appears in-line in Figure 2, but a reader
can instead specify that all non-text elements be represented by
an icon at the right margin and presented in another window only
if selected. Readers can select from a variety of "style sheets"
or presentation specifications that change fonts, type size, or
other presentation characteristics for a particular book or for
the entire library.
The paper clip icon in the right margin indicates a
"bookmark", which users can create to mark and return to
important locations. Another navigation feature shown in Figure
2 in the lower right corner of the window is a Go Back button,
which retraces the reader's steps to re-display previously
displayed books. Readers can also navigate by selecting hypertext
links from entries in an alphabetic "back-of-the-book" index.
Many of the most important features in IRIS InSight,
including structure views, structure-based search, dynamic
reformatting, and alternative presentation styles depend on its
use of SGML. Nevertheless, SGML is both invisible and irrelevant
to IRIS InSight users. To explain how SGML is perceived by
others involved in the overall IRIS InSight effort, we must first
describe the overall publishing process as it currently exists at
Almost all of the technical manuals and other customer-
oriented information that is delivered using IRIS InSight is
initially created by Technical writers, engineers, and other
Silicon Graphics personnel using FrameMaker. Each chapter of a
FrameMaker book is translated into SGML using a customized
FastTag translation program from Avalanche Development of
Boulder, Colorado, and some additional programs written by
Silicon Graphics software engineers. The translation process
involves much more than a tag-for-tag substitution, because much
of the value of getting to SGML is in making hierarchical
structure explicit by inserting new tags that serve as containers
or wrappers around other tags that identify lower structural
The translation programs identify tagging errors in the
FrameMaker files that result from inconsistent or nonstandard
application of FrameMaker tags. Most tagging errors can be
repaired by the author by editing the original file in FrameMaker
and re-running the translation program.
While it might be more efficient to edit the SGML file
directly to fix a tagging or translation problem, this approach
has the drawback for most authors of requiring them to use an
SGML editor, an unfamiliar and non-WYSIWYG tool. Furthermore,
changing the SGML file and not the FrameMaker file would create
two versions of what are supposed to be the same thing.
Insulating authors from SGML by letting them continue to
work in a familiar desktop publishing program has its obvious
advantages. However, since the program does not interactively
enforce compliance with its template or style sheet, the feedback
to the author comes only in batch form after the translation
program is run. Even on a fast Silicon Graphics workstation, an
average chapter can take many minutes to translate to SGML.
After authors have resolved all the tagging problems
reported by the format translation programs, they give the
"clean" SGML files and the corresponding camera-ready hard copy
to production personnel. At this stage all of the tags in the
original FrameMaker files have been converted to SGML tags.
Hypertext links have been derived from the cross reference
markers created by authors in FrameMaker. There is yet no
guarantee, however, that the resulting SGML file completely
conforms to the document type definition (DTD) that formally
defines the structure of a valid document for Silicon Graphics'
SGML application. To validate the SGML files it is necessary to
run them through an SGML parser. The parser is often most useful
in reporting logical omissions in the source file, such as the
lack of a second level heading between first and third level
The validated files are then run through a set of "book
manufacturing" programs that transform the existing back-of-the-
book index into its hypertext counterpart, create the full-text
index needed for the full-text search functions, and build the
other files needed for efficient viewing and navigation of the
book in IRIS InSight. Graphics and images require their own
specialized translation and compression programs before they can
be viewed by IRIS InSight.
The ultimate test of the process is that the book looks and
behaves in IRIS InSight as the author expects it will. In some
situations a book translates from FrameMaker without errors and
is validated by the parser but still needs some minor adjustment
in online formatting. Over time many of these residual problems
have been eliminated by improvements to the FrameMaker templates
or to the translation programs.
Finally, the runtime IRIS InSight files are collected and
prepared for mastering and delivery on CD-ROM.
Because Silicon Graphics authors work with FrameMaker rather
than with SGML authoring tools like those from ArborText or
SoftQuad that directly create SGML files, they need to be
"structure-aware" but do not need specialized knowledge of SGML
syntax or technology. By "structure-aware" we mean they need to
understand the consequences of their use or misuse of FrameMaker
templates and tags. The only knowledge of SGML they need is to be
able to interpret the error messages produced by the format
Production staff at Silicon Graphics, on the other hand,
need more expert knowledge of SGML. They work directly with SGML
source files and SGML tools, and must also maintain the
translation programs that convert from FrameMaker to SGML.
Silicon Graphics managers in technical publications and the
managers of products served by publications organizations do not
much knowledge of SGML, but they need to be structure- and SGML-
aware, in a slightly different way than authors. Both kinds of
managers need to recognize that the benefits of SGML take time to
emerge, and once they do, they accrue to organizations more than
they do to individuals. This realization requires patience and
an appreciation that from an individual author's perspective,
SGML can impose new responsibilities without much perceived value
beyond the productivity gains they experience as end-users of
IRIS InSight. Engineering managers who in the past had little
understanding or interest in technical publications seem to
appreciate that the FrameMaker-to-SGML process imposes an "edit,
compile, debug" cycle on authors that has much in common with the
work of software engineers.
It is a convenient simplification to describe the history of
the IRIS InSight project as involving four primary activities:
- Project initiation and requirements analysis (late 1990-mid 1991)
- Design and development (mid 1991-late 1992)
- Process characterization and institutionalization (late 1991-present)
- Deployment and enhancement (late 1992-present).
A project to develop online documentation can be initiated
for numerous reasons, and a successful project begins by
identifying those that are most important and focusing on them.
A major factor in getting the IRIS InSight effort underway in
late 1990 was the success of a new initiative to deliver software
using CD-ROM. Reducing software distribution costs using CD-ROM
made the cost of shipping printed documentation more visible as a
cost of sales. We were wary that many people would assume that
delivering documentation online was little more than a change of
distribution medium, and we spent considerable time educating
people about the greater challenge posed by online documentation
We recognized that unless the online documents were highly
usable, Silicon Graphics' customers would refuse to give up
printed documents and there would be little cost savings.
Silicon Graphics was about to launch the Indigo workstation, a
low-end (for Silicon Graphics) computer that has since
substantially enlarged its customer base. We knew that this
customer mix has much higher expectations for documentation and
ease of use than the engineering and scientific users who
comprise the high-end graphics computing market that Silicon
Graphics had long dominated. Silicon Graphics couldn't afford an
online documentation system that generated more customer support
calls than it prevented.
An additional factor that motivated the IRIS InSight project
was competitive pressure from other workstation vendors. Other
vendors were already providing online documentation, and this was
beginning to show up in product comparisons, where Silicon
Graphics computers consistently rated outstanding on all factors
except documentation. We turned being last into an advantage by
conducting a careful competitive analysis and resolving to
"leapfrog" the competition with an aggressive online
documentation project that provided new capabilities to users.
Several organizations at Silicon Graphics were considering
online documentation, and it was essential for us to focus these
disparate efforts into a single company-wide initiative. It was
not difficult to convince the managers of projects for whom
online documentation was a third or fourth priority to defer to a
project for which it was the primary focus, but this consensus-
building and consolidation took several months.
In early 1991 we conducted a survey of Silicon Graphics
developers and customers to ask about their plans and
requirements for online document delivery. The results clearly
spelled out four requirements for Silicon Graphics' effort:
- Don't use proprietary technology
- Develop a system that also works on other platforms
- Add additional functionality that takes advantage of Silicon Graphics digital media capabilities
- Use production methods that developers can use as well.
These results seemed somewhat surprising at first. Many
people at Silicon Graphics expected that developers would want a
system that competitively exploited Silicon Graphics' superior
digital media technology. However, since many companies that
develop applications for Silicon Graphics computers also develop
for other Unix computers and the Macintosh, they needed an online
documentation approach that would not be limited to Silicon
Graphics' line. Developers wanted to be able to create a single
set of documents that could be viewed on all of the computers on
which they sold software. IRIS InSight would obviously have to
be standards-based. But which standards?
Our requirements analysis mandated some kind of standards-
based approach for online documentation, but we were not in any
way predisposed to select SGML. We were probably predisposed NOT
to use SGML because we knew initially knew much less about it
than the two alternatives we considered. The first was Adobe's
Postscript, the de facto standard for formatted page description,
already in use by Sun and other vendors as the internal
representation for online documentation, The second was
Microsoft's RTF (Rich Text Format), the ASCII interchange format
for Word that is widely used in the PC marketplace.
We spent several months studying the technical and business
issues and the IRIS InSight engineering team demonstrated that
either Postscript or RTF would satisfy Silicon Graphics'
requirements for delivering online documentation. But what
finally led us to choose SGML was our competitive analysis of the
online documentation offerings of other workstation vendors and
the survey of Silicon Graphics developers. Only SGML would
enable the shift from a vendor-centered "here's our online
documentation" strategy to a customer-centered "here's an online
documentation viewer that you can also use" strategy. The
positive response from the Silicon Graphics developer and
customer base confirms that we made a good decision.
Once we chose SGML and began our system design, we had the
luxury of several "build vs. buy" decisions. Because SGML is a
vendor-independent standard, many companies are building SGML-
based products to support various parts of the SGML publishing
process. We decided that it would let us ship a product faster
and it would be less proprietary if we relied in part on third-
party tools. We chose FastTag from Avalanche Development for
format translation and the DynaText toolkit from Electronic Book
Technologies of Providence, Rhode Island to satisfy some of our
indexing and presentation requirements. Both are technology
leaders in their respective niches.
IRIS InSight takes advantage of the unique digital media
capabilities to present video, audio, 3-D graphics, and animation
on Silicon Graphics computers, but multi-platform developers can
use the basic DynaText viewer to deliver some of this information
on other platforms with no changes to the object files. Without
DynaText, we would be unable to meet the cross-platform
requirement we identified in the 1991 survey of Silicon Graphics
One initial design goal was to maintain fidelity of content
between the printed manuals and those we delivered online. By
this we mean that we would not require page fidelity, an exact
correspondence between online and printed versions in page
numbering, layout, or formatting, but the structural organization
would be the same . The first version of IRIS InSight that we
started shipping in late 1992 more or less met this goal.
But as we have moved more books into IRIS InSight, we have
come to recognize that content fidelity is not entirely
achievable, nor should it be. We have discovered some structural
or logical aspects of our printed books that we cannot preserve
in the online versions. For example, we have no easy way other
than screen snaps to duplicate printed graphics that have text
callouts or the sidenotes that appear in many of our end-user
On the other hand, once a critical mass of information
entered IRIS InSight, users started to rely on the online version
as the primary one, so complete content fidelity would limit us
from enhancing the online books where it added value. We
increased the descriptiveness and number of internal headings in
books because of the effective use that the IRIS InSight
structure view makes of them . We have begun to incorporate
3-D graphics, animation, audio, and video into IRIS InSight
books. We expect that future releases of IRIS InSight will lead
us further from any correspondence with paper documents.
The detailed design of IRIS InSight emerged over time as a
result of a thorough review of the literature, a detailed
analysis of design alternatives, and extensive usability testing.
(We highly recommend ,,). We recognized early that
acceptance of IRIS InSight depended on users being willing to
rely on online documents as their primary version.
Researchers from the customer research and usability
organization at Silicon Graphics conducted three usability
studies with both experienced Silicon Graphics customers and
Silicon Graphics novices. The studies were designed to ensure
that IRIS InSight would be preferred by users and that it
wouldn't generate calls to customer support. These studies
contrasted several specific design alternatives and objectively
measured performance on information retrieval and problem solving
tasks. The most important of these were the "granularity" or
"node size" into which online books should be organized and the
appropriate behavior of hypertext links; e.g., whether to scroll
within the same window or open a second window.
These carefully-controlled experiments led to the final IRIS
InSight design in which books were the most salient online unit
and in which each distinctive link type has a unique behavior.
User performance with the final IRIS InSight design was equal to
that for the printed manuals, a significant achievement given the
limited experience users had with IRIS InSight. Finally, users
strongly preferred IRIS InSight to the printed manuals.
Just as we knew we couldn't design a product with only vague
requirements for putting documents online, we knew we had to
carry out a systematic "re-engineering" effort to examine the
existing end-to-end publications process. In part this caused us
to discover problems that we didn't know we had, such as the
extent to which authors often invented ad hoc tags to meet the
visual requirements for camera-ready copy rather than use only
the official templates and tag sets. Systematizing and
restructuring the publications process was made more difficult by
Silicon Graphics' periodic reliance on contract authors to meet
publications schedules, especially for major product releases,
because contract authors often work from remote locations and are
otherwise removed from the mainstream publications culture.
We gradually recognized that SGML was having a profound
institutional impact at Silicon Graphics and was qualitatively
changing the publications process. We were imposing significant
new responsibilities on technical publications personnel.
SGML changes the relative importance of formatting and
structure. When authors are charged with delivering camera-ready
copy, they are tempted to insert formatting tags until the
document looks just right. A new requirement to deliver valid
SGML files directs an author's attention to more precise
structural tagging that gives customers the advantages of online
presentation but which requires more work . Authors do value the
flexibility provided by the multimedia capabilities of IRIS
InSight, but only if they are given the time to take advantage of
We chose an incremental strategy for moving to SGML that
attempted to minimize the disruption to existing methods and
technology. Because Silicon Graphics had just made a major
investment in technology and training to standardize technical
publications on FrameMaker, we knew we had to design a
publications process based on format translation to SGML from
FrameMaker rather than adopt SGML-based authoring technology
directly. This strategy also preserved Silicon Graphics'
investment in using FrameMaker to create hardcopy documents.
We brought in outside consultants to conduct document
analyses to help us standardize our use of FrameMaker. This was
a critical step, because authoring standards are essential if
automated translation to SGML were to work. We discovered that
although different writing groups at Silicon Graphics had their
own templates, we were able to extract a common document
architecture and encode that in a single document type definition
The DTD is the linchpin of an SGML application because it
formally defines the structure of a valid document instance. It
establishes the target for format translation and is the basis
for the alternative presentation styles in the IRIS InSight
viewer. But what authors see most directly are the templates in
FrameMaker, and any changes to these templates ripple into the
DTD and the software for format translation and online
At the time we didn't fully appreciate this central
importance and vulnerability of the DTD in the overall
publications process. For months several people on the IRIS
InSight team worked on different pieces of the end-to-end
process, and a change that might be an improvement in authoring
templates or other parts viewed in isolation would be a
destabilizing bug to other pieces. It took several months for us
to stabilize the production process.
Training and re-training of authors and production personnel
has been essential. Initially our authors attended courses taught
by popular industry consultants. But as Silicon Graphics has
learned more about SGML and online documentation, there has been
a major shift in training to very specific "here's how we do it
at Silicon Graphics". Our needs can no longer be met by the
broad and relatively unspecific training available from
outsiders. Instead, Silicon Graphics authors have translated
what they learned into Silicon Graphics-speak and it now exists
as a detailed publications style guide as an IRIS InSight book.
This book enables authors to become SGML and IRIS InSight-aware
even if their books are not going online right away. Authors and
production personnel have also instituted one-on-one and group
training in which they teach each other how to write for online
and how to build books successfully.
The production process still needs to be more transparent
for authors. Passage Systems and Silicon Graphics are currently
working on tools for authors and production personnel that will
hide much of the complexity of SGML, especially the nuances of
the format translation and indexing tools.
Bundling IRIS InSight and its core document library for free
as part of system software and charging for printed manuals
overwhelmingly biased the cost-benefit equation in favor of
online documentation. This economic incentive encourages Silicon
Graphics customers to consider relying on online documentation as
their primary version.
We believe it was critical to the success of IRIS InSight
that we focused on issues of putting text online before we moved
to incorporate digital media into IRIS InSight books. It was
difficult at times to maintain this conservative tack, since
Silicon Graphics computers are unsurpassed in their capabilities
for incorporating audio, video, animation, and 3-D graphics.
Nevertheless, we had seen other online documentation efforts fail
because they were seduced by the excitement and hype about
multimedia, leading to books with "Macbeth multimedia" -- full of
sound and fury, but signifying nothing (our apologies to
Shakespeare) . We knew that IRIS InSight would never be
scaleable, cost-effective, or usable by our authors or customers
if we relied on hand-crafted production techniques of the sort
encouraged by premature experimentation with multimedia , .
Now that we have a robust process for converting print-based
books to IRIS InSight, we can confidently provide the FrameMaker
templates, the DTD, and the associated format translation and
production software to those wanting to use IRIS InSight to
become online publishers on their own. Since IRIS InSight text
files are completely compatible with those used by DynaText on
other Unix platforms, the Macintosh, or under Microsoft Windows,
a multi-platform strategy for online documentation is completely
viable. IRIS InSight can use any SGML DTD, so users remain free
to choose another document architecture if they need one for a
specialized application. However, by providing a core of SGML
technology tailored for IRIS InSight, Silicon Graphics and
Passage Systems have greatly reduced both the cost and the risk
of adopting SGML.
SGML enabled Silicon Graphics to design and develop IRIS
InSight, an industry-leading system for delivering online
documentation, while achieving its objective of significantly
reducing the costs of providing that information to customers.
But the transition to SGML involved a steep learning curve. We
had to define an SGML-based publishing process in terms of steps
or functions like authoring, format conversion, indexing,
viewing, and information management so that we could select or
design software to support each activity. This process
characterization took place iteratively, because we didn't have a
complete end-to-end perspective when we started out. When
candidate tools were identified and "plugged into" a tentative
end-to-end solution, the requirements for other pieces were often
unknowingly changed or constrained. We didn't fully appreciate at
the time that the publishing process was both a technological and
an organizational creation that would require significant changes
at Silicon Graphics.
The expertise required to design and develop IRIS InSight
was substantial. We hired numerous consultants, but their
participation then imposed the additional task of integrating
their different perspectives and expertise into what we were
doing on our own.
The substantial increase in the visibility of SGML
technology and concepts today and the benefit of hindsight makes
it easy to say that we made a good decision to use SGML for IRIS
InSight. SGML is certainly viable today for real applications,
and we hope that our case study provides some stepping stones on
a successful path to SGML. Nevertheless, we advise those reading
this paper to recognize that even for us, SGML was only a means
and not an end for online documentation. The ultimate goal was
always usable and cost-effective online documentation.
The IRIS InSight project involved dozens of people in
software engineering, technical publications, release
engineering, usability testing, and customer support
organizations at Silicon Graphics. Avalanche Development,
Electronic Book Technologies, and several external consultants
played essential roles, as did the Silicon Graphics developer
companies who participated as survey respondents and beta sites.
We hope they accept our collective thanks here and appreciate our
concern that if we named them individually we might inadvertently
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