Separation of Content and Form
In the field of technical communication, there is a migration (driven by the need for
efficiency) from style-based, document-centric writing approaches to topic-oriented, modular,
structured authoring techniques.
Fundamental to structured authoring is the concept of the separation of content from
presentation and delivery. The way a piece of text looks during authoring is irrelevant. The
formatting and presentation are post-authoring considerations, and activities possibly not even
performed by a technical writer.
The prime benefit of writing modular content suitable for publication in different forms for
different purposes in different contexts is efficiency: being able to create more in less time.
This benefit is not only applicable to the field of technical communication, but also in other
areas of written communication practice where the drive for greater efficiency suggests a
re-evaluation of writing processes.
Technical Writing Approaches
Technical documentation is a broad term which encompasses computer software and hardware user
guides, corporate policy and procedure manuals, Help systems, scientific and medical
publications, engineering manuals, machinery instructions, reference materials, and many other
forms of non-fiction, corporate, product and business discourse. The word
in the term is sometimes misleading, because the term also encompasses some forms of
organisational communication. Technical documentation is commonly produced by professional
technical writers. For many years, technical writers have followed a document-centric, linear,
narrative writing paradigm, treating a manual as a self-contained and isolated work
(Rockley, 2001). Before computerisation, technical writers wrote drafts in
longhand before sending them for typing, rewriting, editing, reviewing and typesetting. When
word processing software tools were adopted by technical writers, document-centric authoring
programs such as WordPerfect, Word and FrameMaker allowed the same style-based, document-centric
paradigm to be used, but with the technical writer taking over the former roles of typists,
typesetters, layout artists, and in some cases, printers (O'Hara, 2001).
When topic-based, modular writing techniques became known in the early 1990s, the concept of
single sourcing became practicable (Robidoux, 2008, p. 111). Single sourcing is
"a method for developing re-usable information"(Ament, 2003, p. xiii), where re-usable document modules are assembled to form
publications, with different combinations of modules resulting in separate publications. Modular
writing is a technique that makes single-sourcing possible. Modular, or topic-based, writing, is
a style of document design and architecture where content is structured into independent small
modules (topics) which can be assembled into one or many larger texts, such as a books, Web
sites and Help systems. The advent of documentation technologies based on eXtensible Mark-up
Language (XML), at the start of 21st century, expanded the possibilities for single-sourcing and
re-use, and led to the adoption of the philosophy of separation of content and form through
semantic mark-up (Sapienza, 2004, p. 400). XML is a set of standards for the
categorisation, storage and retrieval of all forms of structured information. Practically
speaking, XML is a set of rules for creating information structures, which are known as
In technical communication, the dominant XML application is the Darwin Information Typing
Architecture (DITA). DITA is a semantic mark-up language which incorporates the ideas of
topic-based, modular architecture, standard information structures, and the separation of
content and form.
The schematic following shows how this separation impacts a technical communications team.
Workflow in a DITA authoring environment
DITA has no native presentation format. Mark-up or tagging within DITA simply labels what the
information is, and not what it looks like. A phrase within a sentence may be a window name, and
that is how it is marked up. This approach is known as semantic mark-up. Whether a semantically
marked-up phrase eventually gets displayed in bold, or in red, or in a box, or not at all, is
determined later, outside the authoring process.
Documents are never displayed to the reader in DITA; DITA is not a presentation format.
Content is almost completely separated from presentational form and delivery format. Wherever
possible, context is also separated from content. XML applications represent the progression of
the separation of content and form approach. Earlier attempts at separation can be found in HTML
Separation of Content and Form on the World Wide Web
When Tim Berners-Lee developed the World Wide Web, he, by necessity, incorporated the
principle of the separation of content and form. In those early days, the Internet pipelines
were only capable of carrying very small amounts of information, and Web pages cluttered with
formatting instructions would not be able to be transferred quickly. So Berners-Lee developed
HTML with simple semantics; there were tags for titles, headings, ordered lists, definitions,
quotations, citations, paragraphs, addresses, and so on. There was no provision for indents, or
fonts, or spacing, or alignment, or columns, or even tabs. Presentational rules embedded in the
Web browser determined how a heading would be displayed, how much indent would be applied to
lists, what font paragraphs would be displayed in, and what colour text would be used.
During the period know as the
"browser wars", Netscape and Microsoft added support
in their browsers for new formatting tags, without much consideration to the theoretical
underpinning of the Web (and without approval of the World Wide Web Consortium, the custodians
of Web standards). Thus, font, colour, and other formatting instructions became mixed up with
semantic mark-up, and the benefits of separation were largely lost. It took some years before
the World Wide Web Consortium recovered the situation with the introduction of Cascading Style
Sheets (CSS). While HTML 1.0 left the formatting entirely up to the browser, CSS allowed the
browser to be provided with formatting instructions for an HTML page, separately from the
content itself. The content could reside in an HTML file, and the form could reside in a CSS
By this time, another limitation of HTML had been uncovered: the semantics were too limited.
The solution to this was limitation was XML. From a writing perspective, XML reinforced the
trend to move to structured authoring approaches.
Structured authoring can mean many things, but in the context of this whitepaper, structured
authoring means a standardised, methodological approach to content creation incorporating
systematic labelling, modular, topic-based architecture, constrained writing environments, and
the separation of content and form.
The term structured authoring is applied to a wide variety of writing approaches, to the point
that the meaning is virtually lost. Some say that most technical writing is
"structured writing", because the writing process is approached
in a methodical structured way. According to this definition, all documents with some sort of
structure must have been the result of a structured approach.
Methodological or scientific approaches to writing technical documents became prominent in the
1960s, with Robert Horn's structured writing ideas (later to become Information Mapping) and the
STOP methodology (developed at Hughes-Fullerton) (Tracey et al, 1965) being two of
the intellectual products of that era. The development of SGML almost two decades later enabled
structured approaches to be enforced by software tools. The development of XML in the late 1990s
transformed the way in which knowledge was stored. XML permitted structured information
standards to be created for the storage of knowledge and data for all types of industries. XML
allowed standards such as Chemical Mark-up Language, Mathematics Mark-up Language, Channel
Definition Format, Scaleable Vector Graphics, Open Document Format, and hundreds of others to be
created by industry, government and special interest groups.
A modern definition of what we now mean by structured authoring is:
methodological approach to the creation of content incorporating information types, systematic
use of metadata, XML-based semantic mark-up, modular, topic-based information architecture, a
constrained writing environment with software-enforced rules, content re-use, and the
separation of content and form. "
In the documentation field, new forms of structured writing approaches emerged, enabled by XML
and the new culture of the open source movement. Semantic mark-up was the next stepping stone on
the path to greater separation of content and form.
The use of semantic mark-up in DITA, where text elements are marked up based on their meaning,
allows the content to be essentially separated from its rendition and display to the reader. For
example, a term is marked up as a <term> and a citation as a
<cite>, and no information about how those elements will be
displayed is stored in the content. Stylistic (display) rules are applied when the DITA content
is transformed into a reading format, such as HTML or ink on paper. In a DITA workflow,
documents are created as collections of modular, re-usable topic files, and mechanisms allow not
only the format to be separated from the content, but also the context. The same topic may be a
section in the context of one publication, but a sub-section in the context of another.
By contrast, the intermingling of content, format and context in a style-based document
workflow essentially eliminates the possibility of re-use. Once a paragraph is styled as having
a 13 cm left margin, it cannot be used on paper 12 cm wide. A phrase marked up in italic won't
render as italic on a reading device that doesn't support italic. But a citation identified as a
citation in a DITA topic can be processed to italic by one transformation process, to bold red
by a different transformation process, and to synthesised voice by another transformation
One of the primary means by which DITA delivers efficiency is through
"Automated processing" means that the publishing process (transforming semantically
marked-up source content into a reading format) is wholly automated. Any valid DITA document
should be able to processed in exactly the same way. Automated processing requires a significant
once-off effort to produce the templates that will control the mapping of semantic elements to
presentational formatting, but needs very little on-going effort.
In other words, publishing templates are created to suit the formatting and layout requirement
standards for a company. Once those templates are complete, they are used, without further
intervention, for all that company’s publishing needs, forever. These templates are based on the
company's House Style guidelines. They lock in the presentational style rules.
If each manual produced by a company needs a different presentational style, then automated
"semi-automatic". It means that templates have to be developed for
each manual. Instead of being a once-off effort, the significant cost of creating templates
becomes a recurring cost.
There are consequential benefits of automated processing. Usability is improved by automated
processing, because consistency is a key component of usability. Users find it more difficult to
work with a manual if it looks different to other manuals. Consistency also leads to authority;
users subconsciously associate
"inconsistent presentation" with
If a document is layout-intensive, it is less able to processed automatically. For example, if
a diagram in the left column needs to be lined up with particular paragraphs in the right
column, the mark-up cannot be done in isolation from the publishing process. Another way of
putting it is that the separation of content and form becomes difficult, and that separation of
content and form is what allows:
- reduced cost through automated processing
- reduced translation cost
- reduced cost through content re-use
- value-adding through multi-channel publishing (producing output in many formats)
To explain the impact on content re-use and single-sourcing, we can use the example of the
diagram in the left column aligning with text in the right column. DITA does permit elements to
be marked up with attributes that allow them to be treated specially during processing. We can
use these output attributes to define our column breaks, but this means we end up with
paragraphs that can only be practically used in the context of two column layout with the
diagram to the left. This means we cannot re-use some of those paragraphs in different places in
the manual (or in a different but similar manual), because the content relies on the same
diagram being positioned to the left of the paragraph. Further, we cannot generate the same
content in HTML format for publishing on the Web, because Web browsers
text to suit the user's window size, and HTML doesn't support flow through columns. In other
words, the extra effort expended to make the layout work results in the content being less
In practice, it is very difficult to completely separate content and form. Consider a
table, for example. A table is a formatting construct on the one hand (a method of dividing some
types of content into columns), and a semantic structure for storing reference information (as
in database tables). It is hard to create a table without concern for how it might be presented.
Likewise, an image is both content and form together. The image file contains colour, but also
Distinction between format and style, and data and metadata
In DITA, format has a different meaning to style. Likewise, the meanings of data and metadata
are very different. These distinctions in meaning are important to understanding the broader
concept of the separation of content and form.
"style", as in
"Style Guide", is problematic, because it has a number of
subtly different meanings in this context. Style could mean aesthetic presentational style, and
it could mean writing or wording style. A style could be clean and crisp (aesthetically) while
being ponderous and wordy (stylistically).
To distinguish between the two
"styles", format (or presentational style) should be used
when referring to aesthetic style, or the look and feel of the deliverable document. The term
writing style should be used when referring to the authorial style. In the broader concept of
the separation of content and form, writing style belongs to content, while format belongs to
It is also important to understand the distinction between data and metadata. Data is
analogous to content, while metadata refers to information about the content.
For example, the data of a topic is the information that the reader reads about the subject
matter of the topic. The metadata is the supporting information about the topic that the reader
doesn't normally read or see, such as the creation date, the author, the semantics of the
textual components, and the copyright ownership. Metadata is critical to separation of content
and form, as it stores information that is important for document processing.
Challenges for Technical Communicators
The philosophical differences between style-based authoring and semantic authoring present the
greatest challenges for technical communicators.
In style-based authoring, the structure of a document is defined by the styles applied to its
components. For example, a second level heading might be defined in a document by the
application of a heading 2 style. Likewise, the presentational style of the deliverable document
is defined by styles embedded within the authored document. For example, text to be indented by
2 cm might be defined in the paragraph by the application of an Indent2 style.
The separation of content and form in DITA sees the upper-level structure being defined
outside the content (in the ditamap), and the presentational style being applied in a publishing
process entirely separate from the authoring process. The presentational form for a document can
be unknown to the DITA author. The same topic can have different appearances and different
structures when the same source content is used to produce different deliverable documents.
For example, a DITA topic in one deliverable document may have a heading 2 style applied
during processing, but the same topic in a different deliverable document may have heading 4
applied. The publishing rules determine the mapping of DITA semantic elements to output
Techniques to Learn
Authors moving from style-based authoring to structured authoring will need to build chunking,
labelling and linking skills, and to embrace the technique of separation of content and
DITA authoring in particular requires you to have skills that you may have used in style-based
authoring, but which you will certainly need to use differently. Some skills may be entirely new
to you. These skills are:
- Chunking refers to the way in which you break down information into smaller pieces. The
term is particularly (but not exclusively) used to describe the way in which information is
broadly categorised into information types, or topic types.
- Labelling (or metadata creation)
- Labels and catalogue information are part of a topic's or collection's metadata. Metadata
allows content to be filtered, sorted, processed, and otherwise manipulated. Choosing
accurate labels will result in more flexible documents.
- Linking can be viewed as a technique for defining relationships between topics.
- Separating content from form
- In the writing phase of structured authoring, there is no place for form (format, style
and presentation). Form is not the author's job. Identifying the text's semantics is.
Separation, not Removal
Many objections to the separation ideal rightly point out that format is a vital component of
"separation" is not the same as
"removal". Formatting of the
content is indeed a very critical part of effective documentation. Separation may actually
improve the quality of formatting, because it makes it easier for an expert in form, such as a
graphic designer, to work alongside an expert in writing.
It is true, however, that content and form can seldom be cleanly divided. As Karen McGrane
pointed out in the article WYSIWTF on A List Apart(McGrane, 2013):
" Arguing for separation of content from
presentation implies a neat division between the two. The reality, of course, is that content
and form, structure and style, can never be fully separated. "
Changing focus from form to content may sound easy, but it is turns out to be quite a
difficult transition... writers are so accustomed to working with mixed content and form. The
benefits in separation are many. By automating the formatting process, technical writers can
spend more time on the words and phrasing, rather than on the fonts, alignment and numbering!
This leads to better writing quality, and more consistent presentation.
The advent of a myriad of new reading devices, such as head-up displays in spectacles and
pico-projectors, is making separation of content and form an indispensable tool in
single-sourced, modular, cost-effective documentation.
- Ament, K. (2003). Single sourcing: Building modular documentation (1st ed.). New York:
- McGrane, K. (2013). WYSIWTF An A List Apart Column. A List Apart. Retrieved May 8, 2013,
- O'Hara, F. M. (2001). A Brief History of Technical Communication. In STC Proceedings 2001.
Presented at the 48th International STC Conference, Chicago: Society for Technical
- Rockley, A. (2001). The impact of single sourcing and technology. Technical Communication:
Journal of the Society for Technical Communication, 48(2), 189-199.
- Sapienza, F. (2004). Usability, structured content, and single sourcing with XML. Technical
Communication: Journal of the Society for Technical Communication, 51(3), 399-408.
- Tracey, J. R., Rugh, D. E., & Starkey, W. S. (1965, January). Sequential Thematic
Organization of Publications (STOP): How to Achieve Coherence in Proposals and Reports.