For example, a structured document might identify a certain portion as a "chapter title" (or "code sample" or "quatrain") rather than as "Helvetica bold 24" or "indented Courier".
For example, explicit labeling of "chapter title" or "emphasis" is far more useful to systems for the visually impaired, than merely "Helvetica bold 24" or "italic".
In the same way, meaningful labeling of the many items on a technical information sheet enables far better integration with databases, search systems, online catalogs, and so on.
[1] Structured document systems commonly permit creating explicit rules defining component types and how they may be combined.
Lie and Saarela noted the "Standard Generalized Markup Language (SGML) has pioneered the concept of structured documents",[2] although earlier systems such as Scribe, Augment, and FRESS provided many structured-document features and capabilities, and SGML's offspring XML is now favored.
However, HTML has not only tags for meaning-oriented components such as paragraph, title, and code; but also format-oriented ones such as italic, bold, and most table.
Because the SGML conversion of the Oxford English Dictionary explicitly distinguished the many different meanings which attach to the print version's use of italics, search tools can retrieve entries based on etymology, quotations, and many other features of interest.
When HTML provides structural rather than merely formatting information, visually impaired users can be easily given a more useful reading interface.
When travel companies provide itineraries as structured documents rather than just displays, user tools can easily extract the necessary facts and pass them on to calendar or other applications.