Difference between DAISY 2/DAISY 2.02 and DAISY 3

Original Author(s): Nick Williamson


This article outlines some of the differences between DAISY 2.02 and DAISY 3. At present it does not deal with DAISY 2.

DAISY 3 is the colloquial name for the ANSI/NISO Z39.86-2005 Specifications for the Digital Talking Book.

The DAISY standards can be found in the Standards section of the DAISY consortium web site at: http://www.daisy.org/daisy-standard

The DAISY 3 format has a lot in common with the EPUB format.

Older DAISY players may not be able to play DAISY 3 books.


The DAISY 3 Standard defines an XML file format - called DTBook - for the text part of a book.

The DTBook DTD (document type definition) borrows heavily from the W3C's HTML 4.0 Specification and adds specific structural tags required to accurately and unambiguously represent the content. The DAISY 2.02 Standard defines the text part of a book to be in XHTML which does not have these specific structural tags.

The DTBook format can also be used as the source format for production tools such as the DAISY Pipeline.

Skippable and Escapable Structures

DAISY 3 allows parts of the book to be skipped. If a book has been authored so that footnotes are skippable the user can set their player to automatically skip over them and to indicate that a footnote has been skipped. When the user receives such an indicated they can either allow playback to continue or can tell the player to play the footnote.

DAISY 3 allows parts of the book to be escaped. If a book has been authored so that footnotes are skippable and the user has not set their player to automatically skip over them then, when the player is playing a footnote the user can tell it to escape and continue to play the next part of the book.

Skippable and escapable structures were added to DAISY 2.02 but some players may not support them. Refer to DAISY 2.02 Skippable Structures Recommendation.

Resource File

DAISY 3 allows for “resources” which provide information which is missing from a document or present only in a form inaccessible to the reader.

An example of the use of a resource is to allow the player to describe the different levels of headings in a book as “part”, “section” and “chapter” rather than “heading level 1“, “heading level 2“, “heading level 3“.

Bookmarks and Highlights

DAISY 3 establishes a specific XML file format to support export and import of bookmarks and highlights. A player may allow the user to set bookmarks and to highlight passages in a book, label the marked sections with text or audio notes, and export the resulting collection of marks and notes to other compliant playback devices.

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This page was last edited by DAISY1 on Monday, October 4, 2010 12:02
Text is available under the terms of the DAISY Consortium Intellectual Property Policy, Licensing, and Working Group Process.