Re: [Glossary] Definition of a portable document (and other things...)

A certain amount of adaptation  is necessary before you can call something
"portable." If you create a webpage which is cyan font on a cyan background
on every browser except for Internet Explorer 6, does it matter that the
format *allows* adaptability? I would argue that is not portable document.
Similarly, if you created a website where every aspect of content was
offscreen, and therefore only available to screen reader users, that would
also quite arguably not be portable, by any useful definition. In both of
these cases the formats allow for adaptability, but in neither of these
cases are the documents themselves actually useful if they are in any way
ported.

Given this constraint, "portability," actually has some rather wonderful
implications for accessibility. If a website with all the text only
available to screen reader users (a straw man example) isn't portable, then
it is equally true that a website where all the text is images without alt
(not a straw man at all, as examples exist all over the web) is not
portable.

Adaptability doesn't have to mean a complicated website looks great in
ibooks; it means the essential components of the document are available
when the document's context is changed. (The "graceful degradation" aspect
Ivan and Leonard are discussing upthread.

Deborah