Global and local Navigation

Dear WAI-UA-WG,

I would like to complement the User Agent team for a job well done. On
behalf of the NISO committee developing specifications for Digital talking
Books,I have been asked to pass on some comments about navigation we are
involved in that you might find useful. 

Those of us involved with the development of Digital Talking Books (DTB)
through the NISO effort in conjunction with the DAISY Consortium would like
to explain some navigation and reading concepts we use. We thought this
might be helpful in the final drafting of the User Agent Guidelines. Our
focus has been on the conversion of printed books and their utility in a
digital arena. I'm sure  you will find our comments relevant to the context
of using and reading books. We believe this relates to the web as well. If
you see the need, Please feel free to use any of these concepts. 

TERMS

Global Navigation - (synonym  = navigation )A mechanism to get quickly to a
portion of a book that you want to read.

Local Navigation - (synonym = reading) The process of moving through
information to understand the content.

DESCRIPTIONS

In the arena of DTB we developed a concept of a "Navigation Control Center"
(NCC) which resembles a traditional table of contents, but it is more. The
NCC contains links to all headings at all levels in the book. In addition
to the headings, links to all pages are inserted. Finally we include in the
NCC links to all items that the reader may select to turn off for reading.
For example, if the reader has the automatic reading of footnotes turned
off, there must be a way to quickly get back to that information. For this
reason, the reference to the footnote is placed in the NCC and the reader
can go to the reference, understand the context for the footnote, and then
read the footnote. All items that have the option of turning off automatic
reading can be reached through the NCC.

Once a reader is at a location they wish to start reading, the navigation
process changes. Of course, the reader may elect to read sequentially, but
many times some navigation is needed. Going back or forward one word or
character at a time is used frequently. Moving from one sentence or
paragraph at a time is also needed.  This type of local navigation is
different from the global navigation used to get to the location of what
you want to read. It is frequently desirable to move from one block element
to the next. For example, moving from a paragraph to the next block element
which may be a list, block quote, or sidebar is the normally expected
mechanism for local navigation.

We believe the way a person reads sometimes depends on the construct of the
item they are reading. "Moving into" tables, or lists, or math requires
different navigation options to facilitate reading. This means that the
navigation options are context sensitive.

HOW THIS RELATES TO THE USER AGENT GUIDELINES

Navigating the web is much different than reading a specially prepared DTB.
However, many of the elements are the same. The user on the web follows
links to get to a place that is interesting and then starts to read that
page using the local navigation techniques to understand the content of the
page.  The user agents must allow both global and local navigation to
support reading.

Best
George

George Kerscher, Project Manager
PM to the DAISY Consortium
Recording For the Blind & Dyslexic
Email: kerscher@montana.com
Phone: 406/549-4687

Received on Monday, 29 November 1999 16:35:31 UTC