Copyright © 2024 the Contributors to the Schema.org Accessibility Properties for Discoverability Vocabulary Specification, published by the Accessibility Discoverability Vocabulary for Schema.org Community Group under the W3C Community Contributor License Agreement (CLA) . A human-readable summary is available.
This document defines the recommended vocabularies for use with the Schema.org accessibility properties for discoverability of creative works.
This specification was published by the Accessibility Discoverability Vocabulary for Schema.org Community Group . It is not a W3C Standard nor is it on the W3C Standards Track. Please note that under the W3C Community Contributor License Agreement (CLA) there is a limited opt-out and other conditions apply. Learn more about W3C Community and Business Groups .
GitHub Issues are preferred for discussion of this specification.
The
CreativeWork
type
[
schema-org
]
includes
the
following
accessibility
properties
for
discoverability:
accessibilityAPI
accessibilityControl
accessibilityFeature
accessibilityHazard
accessibilitySummary
accessMode
accessModeSufficient
Although schema.org contains many other properties that describe the accessibility of objects in its taxonomy, these specific properties were developed together as part of a project to improve the discoverability of accessible resources headed by Benetech and IMS Global. Many of these properties were derived directly from the IMS Global AccessForAll (AfA) Information Model Data Element Specification .
Part of this work included defining vocabularies of recommended values for use with these properties to ensure predictability for machine processing. This document represents those vocabularies.
By defining these vocabularies, not only is it simpler for authors to understand and apply the properties, but it ensures that search tools, user agents and other machine intelligence can easily parse and inform users of the information.
The vocabulary defined in this document is a continuation of the work that was informally hosted on the WebSchemas wiki (sometimes referred to as the "version 2.0 accessibility properties"). The project was moved to a W3C Community Group to better formalize the document and increase the transparency of its update process.
For more information about the original project, refer to the Accessibility Metadata Project's web site .
For more information on how to use schema.org accessibility properties not covered by this vocabulary, please refer to their relevant definitions in schema.org.
The values defined in this vocabulary follow a camel casing convention: single words are lowercase, while compound words are concatenated into a single value with a capital letter indicating the start of each connected word (e.g., "alternativeText"). This convention is not applied to acronyms, accessibility APIs, and other values that already have recognized naming conventions (e.g., "MathML" and "iOSAccessibility").
To ensure maximum interoperability with user agents that process these properties, use the values exactly as they are defined in this vocabulary. Alternative case spellings may not be recognized (e.g., "mathml" or "aria").
User agent developers should be aware that these values may not be strictly validated depending on the context in which they are created and used. Two values that differ only in case should be treated as identical.
To extend terms with more information, this vocabulary used to recommend the old slash extension syntax employed by Schema.org until 2015. In this model, extensions of a term are made by adding a slash followed by a refinement term.
Authors are no longer recommended to use this extension mechanism, although the use of slashes is not formally deprecated for backwards compatibility with existing content. The slash syntax was poorly defined, especially when multiple refinements could be specified, making it difficult for machines to process.
When a user may require more information about the characteristics of a resource (e.g., the specifics of what type of braille it contains), it is better to explain these in human-readable terms in an accessibility summary .
If a term in this vocabulary is not be expressive enough, it is now recommended to open an issue in the tracker to consider how to improve the existing term (e.g., by renaming terms or defining more specialized cases).
Indicates that the resource is compatible with the referenced accessibility API.
Compatibility with an accessibility API indicates that assistive technologies on the platform should be able to access the resource.
The property is not applicable to resources that are not tightly integrated with their user interface. It can describe whether a word processing document that only opens in a specific application will work on a given platform, for example, but is not a useful indicator of whether an HTML document will, as there are numerous user agents a user could use to render it.
Setting the property means that the resource is compatible with the given API(s). It does not necessarily mean that the content will be fully accessible to any given user group.
The
expected
value
of
the
accessibilityAPI
property
is
a
list
of
the
compatible
APIs.
For
metadata
formats
incapable
of
expressing
lists,
the
property
should
be
repeated
for
each
API.
Indicates the resource is compatible with the Android Access API .
Indicates
the
resource
uses
ARIA
[
WCAG21
WAI-ARIA
]
markup
to
improve
interoperability
with
platform
APIs.
The
use
of
the
ARIA
value
is
now
deprecated
as
ARIA
is
not
an
accessibility
API.
The
accessibilityFeature
property
value
"
ARIA
"
is
now
recommended
to
use
to
indicate
that
a
resource
makes
use
of
ARIA
to
improve
structural
navigation.
Indicates the resource is compatible with the Accessibility Toolkit (ATK) API [ ATK ] for GNOME.
Indicates the resource is compatible with the Assistive Technology Service Provider Interface (AT-SPI) API [ AT-SPI ] for GNOME.
Indicates the resource is compatible with the BlackBerry Accessibility API .
This value is now obsolete as BlackBerry devices phones and operating systems are no longer developed, sold, or maintained.
After
2016,
the
BlackBerry
name
was
licensed
for
phones
released
using
the
Android
platform.
Compatibility
with
these
devices
must
be
indicated
using
the
AndroidAccessibility
value
.
Indicates the resource is compatible with the Fuchsia Accessibility Framework .
Indicates the resource is compatible with the iAccessible2 API [ IAccessible2 ] for Windows.
Authors should use the NSAccessibility value instead.
Indicates the resource is compatible with the Java Accessibility API [ JAPI ].
Authors should use the UIAccessibility value instead.
Indicates the resource is compatible with the Microsoft Active Accessibility (MSAA) API [ MSAA ] for Windows.
Indicates the resource is compatible with the NSAccessibility API for Apple iOS and tvOS applications built on UIKit.
Indicates the resource is compatible with the UIAccessibility API for macOS applications built on AppKit.
Indicates the resource is compatible with the User Interface Automation API for Windows.
Identifies one or more input methods that allow access to all of the application functionality.
The
accessibilityControl
property
is
used
to
describe
the
ability
of
users
to
interact
with
the
user
interface
controls
that
applications
provide.
The property is not applicable to resources that are not tightly integrated with their user interface. It can describe whether users can control a word processing document that only opens in a specific application, for example, but is not a useful indicator of whether users can control an HTML document, as there are numerous user agent and assistive technology pairings a user could use to access it.
Setting the property means that the specified control method(s) are compatible with the resource.
The
expected
value
of
the
accessibilityControl
property
is
a
list
of
the
applicable
control
methods.
For
metadata
formats
incapable
of
expressing
lists,
the
property
should
be
repeated
for
each
control
method.
Users can fully control the resource through keyboard input.
Users can fully control the resource through mouse input.
Users can fully control the resource through switch input.
Users can fully control the resource through touch input.
Users can fully control the resource through video input.
Users can fully control the resource through voice input.
Content features of the resource, such as accessible media, alternatives and supported enhancements for accessibility.
The
accessibilityFeature
property
provides
a
list
of
all
the
applicable
accessibility
characteristics
of
the
content.
It
allows
a
user
agent
to
discover
these
characteristics
without
having
to
parse
or
interpret
the
structure
of
the
content.
For ease of reading, this section splits the vocabulary into the following distinct groups:
alt
attribute
is
one
of
the
most
commonly
identifiable
augmentation
features.
The
vocabulary
also
includes
the
term
"
none
"
that
authors
can
set
to
indicate
that
the
resource
does
not
contain
special
enhancements.
Similarly,
the
term
"
unknown
"
exists
as
a
placeholder
for
marking
content
that
authors
need
to
review.
The
expected
value
of
the
accessibilityFeature
property
is
a
list
of
the
applicable
features.
For
metadata
formats
incapable
of
expressing
lists,
the
property
should
be
repeated
for
each
feature.
The adaptation terms identify provisions in the content that enable reading in alternative access modes.
Alternative
text
is
provided
for
visual
content
(e.g.,
via
the
[
HTML
]
alt
attribute
).
Audio
descriptions
are
available
(e.g.,
via
an
[
HTML
]
track
element
with
its
kind
attribute
set
to
"
descriptions
").
Indicates that synchronized captions are available for audio and video content.
The
use
of
the
captions
value
is
now
deprecated.
Authors
should
use
the
more
specific
closedCaptions
or
openCaptions
values,
as
appropriate.
Indicates that synchronized closed captions are available for audio and video content.
Closed captions are defined separately from the video, allowing users to control whether they are rendered or not, unlike open captions .
Textual
descriptions
of
math
equations
are
included,
whether
in
the
alt
attribute
for
image-based
equations,
using
the
alttext
attribute
for
[
MathML
]
equations,
or
by
other
means.
Descriptions are provided for image-based visual content and/or complex structures such as tables, mathematics, diagrams, and charts.
Authors
may
set
this
property
independent
of
the
method
they
use
to
provide
the
extended
descriptions
(i.e.,
it
is
not
required
to
use
the
obsolete
[
HTML
]
longdesc
attribute
).
Indicates that synchronized open captions are available for audio and video content.
Open captions are part of the video stream and cannot be turned off by the user, unlike closed captions .
Sign language interpretation is available for audio and video content.
Information about the sign language code used should be provided in the accessibility summary .
Indicates that a transcript of the audio content is available.
The rendering control values identify that access to a resource and rendering and playback of its content can be controlled for easier reading.
Display
Indicates
that
the
display
properties
of
the
content
are
controllable
by
the
user.
This
property
can
be
set,
When setting this property, the author must ensure that the following are modifiable (when applicable to their language and writing mode):
The
preceding
list
may
not
capture
all
needed
display
transformability
characteristics
for
example,
if
custom
CSS
style
sheets
can
be
applied
all
languages.
In
such
cases,
authors
must
ensure
the
missing
characteristics
are
also
transformable
when
setting
this
metadata.
To
request
an
addition
to
the
content
list,
please
open
an
issue
in
the
vocabulary
tracker
.
In addition, text must not be represented as images unless it falls under the exceptions of Success Criterion 1.4.5 [ WCAG2 ].
Note
that
setting
this
property
does
not
mean
that
users
will
be
able
to
control
all
the
appearance.
properties
of
the
display
in
all
user
agents.
It
can
also
be
used
only
indicates
that
the
author
has
not
limited
the
ability
of
users
to
indicate
change
the
settings
(e.g.,
by
using
style
attributes
[
HTML
]
or
!important
declarations
[
css-cascade-4
]
that
styling
in
document
formats
like
prevent
user
agents
from
altering
the
properties,
or
by
restricting
users
from
modifying
Word
and
or
PDF
can
files).
The
property
must
not
be
modified.
set
for
content
for
which
no
user
agents
are
available
that
can
transform
the
appearance
and
presentation
of
the
text.
Describes a resource that offers both audio and text, with information that allows them to be rendered simultaneously. The granularity of the synchronization is not specified. This term is not recommended when the only material that is synchronized is the document headings.
For content with timed interaction, this value indicates that the user can control the timing to meet their needs (e.g., pause and reset)
No digital rights management or other content restriction protocols have been applied to the resource.
The specialized markup terms identify content available in specialized markup grammars. These grammars typically provide users with enhanced structure and navigation capabilities.
Identifies that chemical information is encoded using the ChemML markup language .
Identifies that mathematical equations and formulas are encoded in the LaTeX typesetting system .
Identifies that mathematical equations and formulas are encoded in [ MathML ].
One or more of [ SSML ], [ Pronunciation-Lexicon ], and [ CSS3-Speech ] properties has been used to enhance text-to-speech playback quality.
The clarity terms identify ways that the content has been enhanced for improved auditory or visual clarity.
Audio
content
with
speech
in
the
foreground
meets
the
contrast
thresholds
set
out
in
WCAG
Success
Criteria
1.4.7
.
[
WCAG2
].
Information about the how the audio meets the requirement should be provided in the accessibility summary (i.e., there is no background noise, at least 20db difference between foreground speech and background noise, or the background noise can be turned off.)
Content
meets
the
visual
contrast
threshold
set
out
in
WCAG
Success
Criteria
1.4.6
.
[
WCAG2
].
The content has been formatted to meet large print guidelines.
The
property
is
not
set
if
the
font
size
can
be
increased.
See
displayTransformability
.
Information about the type of large print (e.g., the font size) should be provided in the accessibility summary .
The tactile terms identify content that is available in tactile form.
The content is in braille format, or alternatives are available in braille.
Information about the type of braille (e.g., ASCII, unicode, nemeth), whether the braille is contracted or not, and what code the braille conforms to should be provided in the accessibility summary .
When used with creative works such as books, indicates that the resource includes tactile graphics.
When used to describe an image resource or physical object, indicates that the resource is a tactile graphic.
Refer to the BANA Guidelines and Standards for Tactile Graphics for more information about tactile graphic formats and formatting.
When used with creative works such as books, indicates that the resource includes models to generate tactile 3D objects.
When used to describe a physical object, indicates that the resource is a tactile 3D object.
The internationalization terms identify those accessibility characteristics of the content which are required for internationalization.
Indicates that ruby annotations [ JLreq ] are attached to every CJK ideographic character in the content. Ruby annotations are used as pronunciation guides for the logographic characters for languages like Chinese or Japanese. They make difficult CJK ideographic characters more accessible.
If
some
but
not
all
CJK
ideographic
characters
have
ruby
annotations,
use
the
rubyAnnotations
value.
Indicates
that
the
content
can
be
laid
out
horizontally
(e.g,
using
the
horizontal-tb
writing
mode
of
[
css-writing-modes-3
]).
This
value
should
only
be
set
when
the
language
of
the
content
allows
both
horizontal
and
vertical
directions.
Notable
examples
of
such
languages
are
Chinese,
Japanese,
and
Korean.
Some dyslexic Japanese can read horizontal writing but cannot read vertical writing.
Indicates that ruby annotations are attached to some but not all CJK ideographic characters in the content.
If
all
CJK
ideographic
characters
have
ruby
annotations,
use
the
fullRubyAnnotations
value.
Indicates
that
the
content
can
be
laid
out
vertically
(e.g,
using
the
vertical-rl
of
[
css-writing-modes-3
]).
This
value
should
only
be
set
when
the
language
of
the
content
allows
both
horizontal
and
vertical
directions.
Indicates that the content can be rendered with additional word segmentation.
Although the space character is not typically used for word segmentation in languages such as Chinese, Japanese, Thai and Lao, it may be used for accessibility reasons.
Indicates that the content can be rendered without additional word segmentation.
Indicates that the resource does not contain any accessibility features.
The
none
value
must
not
be
set
with
any
other
feature
value.
Indicates that the author has not yet checked if the resource contains accessibility features. This value is only intended as a placeholder until an accessibility review can be completed.
The
unknown
value
must
not
be
set
with
any
other
feature
value.
A characteristic of the described resource that is physiologically dangerous to some users. Related to WCAG 2.0 guideline 2.3 .
Identifying potential hazards that a resource poses allows users to determine if a resource poses a risk to them and to potentially filter out content that could be harmful.
The
expected
value
of
the
accessibilityHazard
property
is
a
list
of
the
applicable
hazards.
For
metadata
formats
incapable
of
expressing
lists,
the
property
should
be
repeated
for
each
hazard.
The
accessibilityHazard
property
currently
allows
three
types
of
hazards
to
be
identified:
flashing,
motion
simulation,
and
sound.
These
correspond
to
the
values
flashing
,
motionSimulation
,
and
sound
.
It
also
allows
authors
to
indicate
that
each
of
the
hazards
is
not
present.
In
this
case,
the
values
follow
the
pattern
"
no…Hazard
",
using
the
hazard
names
in
place
of
the
ellipsis
(e.g.,
noFlashingHazard
).
If
the
author
is
sure
there
are
no
hazards,
they
are
recommended
to
use
the
value
"
none
"
in
place
of
specifying
that
each
individual
hazard
is
not
present.
When
setting
this
value,
no
other
hazard
statuses
are
allowed.
Authors
can
additionally
indicate
that
they
are
unable
to
determine
if
a
hazard
is
present.
In
this
case,
the
values
follow
the
pattern
"
unknown…Hazard
",
using
the
hazard
names
in
place
of
the
ellipsis
(e.g.,
unknownSoundHazard
).
Authors
can
set
the
value
unknown
if
they
are
unsure
whether
any
hazards
are
present
(e.g.,
because
they
do
not
know
how,
or
are
unable,
to
assess
them).
When
setting
this
value,
no
other
hazard
statuses
are
allowed.
Indicates
that
the
resource
presents
a
flashing
hazard
for
photosensitive
persons.
This
value
should
be
set
when
the
content
meets
the
hazard
thresholds
described
in
Success
Criterion
2.3.1
Three
Flashes
or
Below
Threshold
[
WCAG2
].
Indicates that the resource presents a flashing hazard for photosensitive persons.
The
flashing
value
must
not
be
set
when
any
of
the
noFlashingHazard
,
unknownFlashingHazard
,
none
,
or
unknown
values
is
set.
Indicates that the resource contains instances of motion simulation that may affect some individuals.
Some examples of motion simulation include video games with a first-person perspective and CSS-controlled backgrounds that move when a user scrolls a page.
The
motionSimulation
value
must
not
be
set
when
any
of
the
noMotionSimulationHazard
,
unknownMotionSimulationHazard
,
none
,
or
unknown
values
is
set.
Indicates that the resource contains auditory sounds that may affect some individuals.
The application of this value is currently under discussion as its application is underspecified.
The
sound
value
must
not
be
set
when
any
of
the
noSoundHazard
,
unknownSoundHazard
,
none
,
or
unknown
values
are
set.
Indicates that the resource does not contain any hazards.
It
is
recommended
to
use
the
none
value
when
there
are
no
hazards
instead
of
individual
statements
for
noSoundHazard
,
noMotionSimulationHazard
,
and
noFlashingHazard
.
The
none
value
must
not
be
set
when
specifying
either
a
known
hazard
or
the
unknown
value.
It
should
not
be
set
when
negative
hazard
claims
are
made.
Indicates that the resource does not present a flashing hazard.
The
noFlashingHazard
value
must
not
be
set
when
any
of
the
flashing
,
unknownFlashing
,
or
unknown
values
is
set.
It
should
not
be
set
when
the
none
value
is
set.
Indicates that the resource does not contain instances of motion simulation.
The
noMotionSimulation
value
must
not
be
set
when
any
of
the
motionSimulation
,
unknownMotionSimulationHazard
,
or
unknown
values
is
set.
It
should
not
be
set
when
the
none
value
is
set.
Indicates that the resource does not contain auditory hazards.
The application of this value is currently under discussion as its application is underspecified.
The
noSoundHazard
value
must
not
be
set
when
either
of
the
sound
,
unknownSoundHazard
,
or
unknown
values
is
set.
It
should
not
be
set
when
the
none
value
is
set.
Indicates that the author is not able to determine if the resource presents any hazards.
It
is
recommended
to
use
the
unknown
value
when
all
hazards
are
unknown
instead
of
individual
statements
for
unknownSoundHazard
,
unknownMotionSimulationHazard
,
and
unknownFlashingHazard
.
The
unknown
value
must
not
be
set
when
specifying
either
a
known
hazard
or
the
none
value.
It
should
not
be
set
with
the
individual
unknown
hazard
value.
Indicates that the author cannot determine if a flashing hazard exists.
The
unknownFlashingHazard
value
must
not
be
set
when
any
of
the
flashing
,
noFlashingHazard
,
none
values
is
set.
It
should
not
be
set
when
the
unknown
value
is
set.
Indicates that it is unknown if a motion simulation hazard exists within the content.
The
unknownMotionSimulation
value
must
not
be
set
when
any
of
the
motionSimulation
,
noMotionSimulationHazard
or
none
values
is
set.
It
should
not
be
set
when
the
unknown
value
is
set.
Indicates that it is unknown if an auditory hazard exists within the content.
The
unknownSoundHazard
value
must
not
be
set
when
either
of
the
sound
,
unknownSoundHazard
,
or
unknown
values
is
set.
It
should
not
be
set
when
the
none
value
is
set.
A human-readable summary of specific accessibility features or deficiencies, consistent with the other accessibility metadata but expressing subtleties such as "short descriptions are present but long descriptions will be needed for non-visual users" or "short descriptions are present and no long descriptions are needed."
The
accessibilitySummary
property
is
a
free-form
field
that
allows
authors
to
describe
the
accessible
properties
of
the
resource.
As
a
result,
it
does
not
have
an
associated
vocabulary.
The human sensory perceptual system or cognitive faculty through which a person may process or perceive information.
The
accessMode
property
describes
the
ways
information
is
encoded
in
the
resource,
where
information
is
defined
as
any
content
that
contributes
to
the
understanding
of
the
resource.
The
expected
value
of
the
accessMode
property
is
a
list
of
the
applicable
access
modes.
For
metadata
formats
incapable
of
expressing
lists,
the
property
should
be
repeated
for
each
access
mode.
The access modes do not tell users if all the specified modes are necessary to consume the information or if only individual modes or combinations are necessary (e.g., in a book with audio content, the ability to read textual content may be sufficient if transcripts are provided).
The
accessModeSufficient
property
is
designed
to
fill
this
gap
of
understanding
the
combinations
of
modes
necessary
to
fully
consume
the
information.
Indicates that the resource contains information encoded in auditory form.
This value is not set when the auditory content conveys no information. For example, an instructional video might include background music while all the necessary information to complete the task is conveyed visually and/or through text captions.
Indicates that the resource contains charts encoded in visual form.
Indicates that the resource contains chemical equations encoded in visual form.
Indicates that the resource contains information encoded such that color perception is necessary.
Indicates that the resource contains diagrams encoded in visual form.
Indicates that the resource contains mathematical notations encoded in visual form.
Indicates that the resource contains musical notation encoded in visual form.
Indicates that the resource contains information encoded in tactile form.
Note that although an indication of a tactile mode often indicates the content is encoded using a braille system, this is not always the case. Tactile perception may also indicate, for example, the use of tactile graphics to convey information.
Indicates that the resource contains text encoded in visual form.
Indicates that the resource contains information encoded in textual form.
This value is not set if the only textual content is for navigational purposes. For example, an audiobook might include a table of contents, but it is not necessary to read the table of contents to read the work. Likewise, books with synchronized text-audio playback may only include headings to allow structured navigation.
Indicates that the resource contains information encoded in visual form.
This value is not set if the only visual imagery is presentational or not directly relevant to understanding the content. Examples of this type of imagery include cover images for publications, corporate logos, and purely decorative images.
A list of single or combined accessModes that are sufficient to understand all the intellectual content of a resource.
Although the access modes indicate how the information is encoded in its default form, knowing the encoding only describes one possible perceptual pathway through the content. For example, a book with textual and visual content will, at the most basic level, require an individual who can read text and view images.
The author of the content may, however, provide alternatives to a specific access mode that allow the content to be wholly consumed in another manner. The use of alternative text and extended descriptions, for example, can allow a user who cannot perceive visual content to read all the information in textual form (e.g., through text-to-speech playback).
In such a case, a resource with textual and visual access modes could have both a textual and visual sufficient access mode and a purely textual access mode — because there are text equivalents for the visual content. Specifying there is an additional textual-only pathway through the content allows users of screen readers, for example, to recognize that the content will be readable by them.
It is for this reason that content that has multiple access modes may have one or more sets of sufficient access modes: each listing of sufficient access modes provides users with one possible combination of reading modes that allow the content to be read in full.
Although listing the combinations of access modes that allow a user to read all the content is helpful, the most important sufficient access modes to list are the single-value ones. Users looking for an alternative to the default encoding of the content typically are looking for a single presentation mode (e.g., a fully textual pathway to use with a text-to-speech renderer or a fully auditory pathway to listen to).
The
expected
value
of
the
accessModeSufficient
property
is
an
ItemList
.
Each
entry
in
the
ItemList
must
be
a
list
of
one
or
more
access
modes
representing
one
pathway.
For formats incapable of expressing lists, the property should be repeated for each set of sufficient access modes. In these cases, it is recommended to use a comma-separated list of values.
Indicates that auditory perception is necessary to consume the information.
Indicates that tactile perception is necessary to consume the information.
Indicates that the ability to read textual content is necessary to consume the information.
Note that reading textual content does not require visual perception, as textual content can be rendered as audio using a text-to-speech capable device or assistive technology.
Indicates that visual perception is necessary to consume the information.
The following example shows how accessibility metadata could be used to enhance a library record available on the Web.
<div itemscope="" itemtype="http://schema.org/Book">
<meta itemprop="bookFormat" content="EBook/DAISY3" />
<meta itemprop="accessibilityFeature" content="ARIA" />
<meta itemprop="accessibilityFeature" content="largePrint" />
<meta itemprop="accessibilityFeature" content="highContrastDisplay" />
<meta itemprop="accessibilityFeature" content="displayTransformability" />
<meta itemprop="accessibilityFeature" content="longDescription" />
<meta itemprop="accessibilityFeature" content="alternativeText" />
<meta itemprop="accessibilityFeature" content="readingOrder" />
<meta itemprop="accessibilityFeature" content="structuralNavigation" />
<meta itemprop="accessibilityFeature" content="tableOfContents" />
<meta itemprop="accessibilityControl" content="fullKeyboardControl" />
<meta itemprop="accessibilityControl" content="fullMouseControl" />
<meta itemprop="accessibilityHazard" content="none" />
<dl>
<dt>Name:</dt>
<dd itemprop="name">Holt Physical Science</dd>
<dt>Brief Synopsis:</dt>
<dd itemprop="description">NIMAC-sourced textbook</dd>
<dt>Long Synopsis:</dt>
<dd>N/A</dd>
<dt>Book Quality:</dt>
<dd>Publisher Quality</dd>
<dt>Book Size:</dt>
<dd itemprop="numberOfPages">598 Pages</dd>
<dt>ISBN-13:</dt>
<dd itemprop="isbn">9780030426599</dd>
<dt>Publisher:</dt>
<dd itemprop="publisher" itemtype="http://schema.org/Organization" itemscope="">Holt, Rinehart
and Winston</dd>
<dt>Date of Addition:</dt>
<dd>06/08/10</dd>
<dt>Copyright Date:</dt>
<dd itemprop="copyrightYear">2007</dd>
<dt>Copyrighted By:</dt>
<dd itemprop="copyrightHolder" itemtype="http://schema.org/Organization" itemscope="">Holt,
Rinehart and Winston</dd>
<dt>Adult content:</dt>
<dd><meta itemprop="isFamilyFriendly" content="true" />No</dd>
<dt>Language:</dt>
<dd><meta itemprop="inLanguage" content="en-US" />English US</dd>
<dt>Essential Images:</dt>
<dd>861</dd>
<dt>Described Images:</dt>
<dd>910</dd>
<dt>Categories:</dt>
<dd><span itemprop="genre">Educational Materials</span></dd>
<dt>Grade Levels:</dt>
<dd>Sixth grade, Seventh grade, Eighth grade</dd>
<dt>NIMAC:</dt>
<dd>This book is currently only available to public K-12 schools and organizations in the United
States for use with students with an IEP, because it was created from files supplied by the
NIMAC under these restrictions. Learn more in the NIMAC Support Center.</dd>
</dl>
<div class="bookReviews" itemprop="aggregateRating" itemscope=""
itemtype="http://schema.org/AggregateRating">
<h2>Reviews of Holt Physical Science (<span itemprop="reviewCount">0</span> reviews)</h2>
<div class="bookReviewScore">
<span><span itemprop="ratingValue">0</span> - No Rating Yet</span>
</div>
</div>
</
div
>
This example shows how the accessibility metadata could be used to augment a record for a video.
<dl itemtype="http://schema.org/VideoObject" itemscope="">
<dt>Title:</dt>
<dd itemprop="name">Arctic Climate Perspectives</dd>
<dt>Description:</dt>
<dd itemprop="description">This video, adapted from material provided by the ECHO
partners, describes how global climate change is affecting Barrow, Alaska.</dd>
<dt>Adaptation Type:</dt>
<dd><span itemprop="accessibilityFeature">captions</span></dd>
<dt>Access Mode:</dt>
<dd>auditory, visual</dd>
<dt>URL:</dt>
<dd><a itemprop="url" href="http://www.example.org/asset/echo07_vid_climate"
>http://www.example.org/asset/echo07_vid_climate</a>/</dd>
<dt>Has Adaptation:</dt>
<dd>http://www.example.org/asset/echo07_vid_climate_dvs/</dd>
<dt>Subjects:</dt>
<dd><span itemprop="about">National K-12 Subject::Science::Earth and Space
Science::Water Cycle, Weather, and Climate::Structure and Composition of the
Atmosphere, National K-12 Subject::Science::Earth and Space Science::Water Cycle,
Weather, and Climate::Climate</span></dd>
<dt>Education Level:</dt>
<dd>Grade 6, Grade 7, Grade 8, Grade 9</dd>
<dt>Audience:</dt>
<dd><span itemprop="intendedEndUserRole">Learner</span></dd>
<dt>Resource Type:</dt>
<dd><span itemprop="genre">Audio/Visual</span>,
<span itemprop="genre">Movie/Animation</span></dd>
<dt>Language:</dt>
<dd><span itemprop="inLanguage">en-US</span></dd>
<dt>Publication Date:</dt>
<dd itemprop="datePublished">2007-02-12</dd>
<dt>Rights:</dt>
<dd>Download and Share, <a itemprop="useRightsUrl"
href="http://www.example.org/oerlicense/2/"
>http://www.example.org/oerlicense/2/</a></dd>
</
dl
>
Note that this change log only identifies substantive changes to the vocabulary — those that add or deprecate terms, or are similarly noteworthy.
For a list of all issues addressed (typos, minor definition modifications, etc.), refer to the Community Group's issue tracker .
FuchsiaAccessibility
to
the
accessibilityAPI
values.
See
issue
24
.
closedCaptions
and
openCaptions
to
replace
the
more
generic
captions
value.
See
issue
26
.
unknown
feature
for
placeholder
use.
See
issue
17
.
pageNavigation
feature
for
indicating
that
a
resource
has
a
page
list.
See
issue
6
.
pageBreakMarkers
feature
for
indicating
that
a
resource
includes
static
page
break
markers.
printPageNumbers
is
retained
as
a
synonym
but
no
longer
recommended
for
use.
See
issue
6
.
bookmarks
feature
due
to
its
ambiguous
definition.
The
tableOfContents
and
annotations
values
are
recommended
in
its
place.
See
issue
5
.
accessibilityFeature
.
See
pull
request
39
.
accessibilityAPI
value
"ARIA"
is
deprecated.
It
is
replaced
by
a
new
"ARIA"
value
for
accessibilityFeature
for
indicating
the
use
of
roles
of
enhanced
structural
and
landmark
navigation.
See
issue
4
.
The editors would like to thank the Accessibility Discoverability Vocabulary for Schema.org Community Group participants for their ongoing input and suggestions to improve this vocabulary.
Additional thanks go to the original participants of the Accessibility Metadata Project for their work bringing the properties and vocabularies to reality.