Try again: PDF Technology section

Introduction



The Portable Document Format (PDF) is a file format for representing
documents in a manner independent of the application software, hardware, and
operating system used to create them, as well as of the output device on
which they are to be displayed or printed. PDF files specify the appearance
of pages in a document in a reliable, device-independent manner. The PDF
specification was introduced by Adobe Systems in 1993.

The origins of PDF and the Adobe® Acrobat® product family date to early
1990. At that time, the PostScript® page description language was a standard
for the production of the printed page. PDF builds on the PostScript page
description language by layering a document structure and interactive
navigation features on PostScript’s underlying imaging model, providing a
convenient, efficient mechanism for enabling documents to be reliably viewed
and printed anywhere.

PDF is an International Standard

PDF is an International Standard: PDF 1.7 (ISO 32000-1).

On January 29, 2007, Adobe Systems Incorporated announced its intention to
release the full Portable Document Format (PDF 1.7) specification to the
American National Standard Institute (ANSI) and the Enterprise Content
Management Association (AIIM), for the purpose of publication by the
International Organization for Standardization (ISO). In January 2008, this
ISO technical committee approved the final revised documentation for PDF 1.7
as an international standard.

The PDF specification was first published at the same time the first Acrobat
products were introduced in 1993.

As the format evolved, specialized subsets of the full PDF specification
were developed to meet specific technical requirements. These subsets became
standards published by the International Organization for Standards (ISO) or
are in the process of standardization. Of note for accessibility is PDF/UA.

PDF/UA (Universal Accessibility) became an ISO Draft International Standard
(DIS) in November 2010 (ISO/DIS 14289-1). (See PDF/UA Wiki (ISO DIS 14289 -
1).) The scope of PDF/UA is not meant to be a techniques (how-to)
specification, but rather a set of guidelines for creating accessible PDF.
The specification describes the required and prohibited components and the
conditions governing their inclusion in or exclusion from a PDF file in
order for the file to be available to the widest possible audience,
including those with disabilities. The mechanisms for including the
components in the PDF stream are left to the discretion of the individual
developer, PDF generator, or PDF viewing agent. PDF/UA also specifies the
rules governing the behavior for a conforming reader.


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Thanks,

AWK

> -----Original Message-----

> From: Loretta Guarino Reid [mailto:lorettaguarino@google.com]

> Sent: Wednesday, April 13, 2011 4:38 PM

> To: Andrew Kirkpatrick; Mary Utt

> Cc: WCAG Editors

> Subject: PDF Technology Notes

>

> Andrew,

>

> Concerns have been raised about the PDF Technology Notes having much too
much of a marketing feel, and having strayed pretty far from the goals of
providing common user agent notes. We'll need to get them revised before we
can release a public draft.

>

> Can we remove the Introduction (that is, the info up to PDF Accessibility
Support), Mary, I see there are some conversion problems in this document,
too (weird text at the beginning of headings). I don't know whether you can
fix them or whether this is something that Michael needs to fix.