Re: Accessibility and Web Standards

On Wed, 2002-07-10 at 02:05, John Colby wrote:
> My second thoughts concern the use of the term accessible - and the
> task we have in promoting improved accessibility as a natural
> consequence of adopting web standards. How should it be explained?

I am by no means an expert in this area, but this question got me
thinking, and I wanted to write it down.  I haven't read the
accessibility docs in a long time, so I don't remember if there was a
definition in there, and I don't know if this is even what you were
looking for, but I will take a stab at a formal definition of how /I/
define and explain the term accessible:


Take any document such as a novel, magazine, or newspaper.  These
documents are more than just a sequence of hieroglyphs - they have
attributes such as whitespace, fonts, and color - this is
"presentation".  Presentation is the syntax of a document, this syntax
is used to convey semantics.  At the most basic level, we (normally) use
the syntax of whitespace (and punctuation) to define a sequence of
hieroglyphs semantically as words, sentences, and paragraphs.  At a
higher level we often use presentation such as large font sizes or color
to convey the semantic of headings, and italics to convey emphasis. 
These semantics are what constitute a documents structure.  The mapping
of syntax to semantics - presentation to structure - (and back) - is not
universal.  The mapping is effected by everything from the medium being
used (visual/auditory), to the culture defining the presentation
(language/text direction), to limitations in peoples ability to perceive
a given presentation (deaf/blind).  Knowing the structure of a document
facilitates the ability for creation of a mapping from it's structure to
a presentation suitable for a particular viewer - this is accessibility.


-- 
Chris Hubick
mailto:chris@hubick.com
http://www.hubick.com/

Received on Wednesday, 10 July 2002 05:53:04 UTC