This document is also available in this non-normative format: diff to previous version .
Copyright
©
2011
2012
W3C
®
(
MIT
,
ERCIM
,
Keio
),
All
Rights
Reserved.
W3C
liability
,
trademark
and
document
use
rules
apply.
RDFa
Lite
is
a
small
minimal
subset
of
RDFa
consisting
of
a
few
attributes
that
may
be
applied
to
most
simple
to
moderate
structured
data
markup
tasks.
While
it
is
not
a
complete
solution
for
advanced
markup
tasks,
it
does
provide
a
good
entry
point
work
for
beginners.
most
day-to-day
needs
and
can
be
grasped
by
most
Web
authors
with
minimal
effort.
This section describes the status of this document at the time of its publication. Other documents may supersede this document. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at http://www.w3.org/TR/.
This
document
was
published
by
the
W3C
RDF
Web
Applications
Working
Group
as
a
First
Public
Last
Call
Working
Draft.
The
purpose
of
this
document
is
to
provide
an
easy
15
minute
introduction
to
RDFa
that
will
resonate
with
most
Web
developers.
This
document
is
not
intended
to
be
a
complete
specification
of
RDFa
1.1.
The
complete
specification
of
RDFa
can
be
found
in
RDFa
Core
or
one
of
the
host
languages
for
RDFa:
XHTML+RDFa,
SVG+RDFa,
or
HTML+RDFa.
This
document
is
intended
to
become
a
W3C
Recommendation.
If
you
wish
to
make
comments
regarding
this
document,
please
send
them
to
public-rdfa-wg@w3.org
(
subscribe
,
archives
).
The
Last
Call
period
ends
21
February
2012.
All
feedback
is
welcome.
Publication as a Working Draft does not imply endorsement by the W3C Membership. This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.
This is a Last Call Working Draft and thus the Working Group has determined that this document has satisfied the relevant technical requirements and is sufficiently stable to advance through the Technical Recommendation process.
This document was produced by a group operating under the 5 February 2004 W3C Patent Policy . W3C maintains a public list of any patent disclosures made in connection with the deliverables of the group; that page also includes instructions for disclosing a patent. An individual who has actual knowledge of a patent which the individual believes contains Essential Claim(s) must disclose the information in accordance with section 6 of the W3C Patent Policy .
This section is non-normative.
The
full
RDFa
syntax
[
RDFA-CORE
]
is
often
criticized
as
having
too
much
functionality,
leaving
first-time
provides
a
number
of
basic
and
advanced
features
that
enable
authors
confused
about
the
more
to
express
fairly
complex
structured
data,
such
as
relationships
among
people,
places,
and
events
in
an
HTML
or
XML
document.
Some
of
these
advanced
features.
features
may
make
it
difficult
for
authors,
who
may
not
be
experts
in
structured
data,
to
use
RDFa.
This
lighter
version
of
RDFa
helps
authors
easily
jump
into
is
a
gentler
introduction
to
the
world
of
structured
data,
intended
for
authors
that
want
to
express
fairly
simple
data
world.
in
their
web
pages.
The
goal
was
is
to
create
provide
a
very
minimal
subset
that
is
easy
to
learn
and
will
work
for
80%
of
the
folks
out
there
authors
doing
simple
data
markup.
This section is non-normative.
RDFa
Lite
consists
of
five
simple
attributes;
vocab
,
typeof
,
property
,
about
,
and
prefix
.
RDFa
1.1
Lite
is
completely
upwards
compatible
with
the
full
set
of
RDFa
1.1
attributes.
This
means
that
if
an
author
finds
that
RDFa
Lite
isn't
powerful
enough,
transitioning
to
the
full
version
of
RDFa
is
just
a
matter
of
adding
the
more
powerful
RDFa
attributes
into
the
existing
RDFa
Lite
markup.
RDFa,
like
Microformats
[
MICROFORMATS
]
and
Microdata,
allow
Microdata
[
MICRODATA
],
enables
us
to
talk
about
things
on
the
Web.
Web
such
that
a
machine
can
understand
what
we
are
saying.
Typically
when
we
talk
about
a
thing,
we
use
a
particular
vocabulary
to
talk
about
it.
So,
if
you
wanted
to
talk
about
People,
the
vocabulary
that
you
would
use
would
specify
terms
like
name
and
telephone
number
.
When
we
want
to
mark
up
things
on
the
Web,
we
need
to
do
something
very
similar,
which
is
specify
which
vocabulary
that
we
are
going
to
be
using.
Here
is
a
simple
example
that
specifies
a
vocabulary
that
we
intend
to
use
to
markup
things
in
the
paragraph:
<p vocab="http://schema.org/">
My name is Manu Sporny and you can give me a ring via 1-800-555-0199.
</p>
As
you
will
note
above,
In
this
example
we
have
specified
that
we're
we
are
going
to
be
using
the
vocabulary
that
can
be
found
at
http://schema.org/
.
This
is
a
vocabulary
that
has
been
released
by
major
search
engine
companies
to
talk
about
common
things
on
the
Web
that
Search
Engines
care
about
–
things
like
People,
Places,
Reviews,
Recipes,
and
Events.
Once
we
have
specified
the
vocabulary,
we
need
to
specify
the
type
of
the
thing
that
we're
talking
about.
In
this
particular
case
we
are
talking
about
a
Person,
which
can
be
marked
up
like
so:
<p vocab="http://schema.org/" typeof="Person">
My name is Manu Sporny and you can give me a ring via 1-800-555-0199.
</p>
Now
all
we
need
to
do
is
specify
which
properties
of
that
person
we
want
to
point
out
to
the
search
engine.
In
the
following
example,
we
mark
up
the
person's
name
and
name,
phone
number:
number
and
web
page.
Both
text
and
URLs
can
be
marked
up
with
RDFa
Lite.
In
the
following
example,
pay
particular
attention
to
the
types
of
data
that
are
being
pointed
out
to
the
search
engine,
which
are
highlighted
in
blue:
<p vocab="http://schema.org/" typeof="Person"> My name is<span >Manu Sporny</span><span property="name">Manu Sporny</span> and you can give me a ring via<span >1-800-555-0199</span>.<span property="telephone">1-800-555-0199</span> or visit <a property="url" href="http://manu.sporny.org/">my homepage</a>. </p>
Now, when somebody types in “phone number for Manu Sporny” into a search engine, the search engine can more reliably answer the question directly, or point the person searching to a more relevant Web page.
If you want Web authors to be able to talk about the things on your page, you can identify the thing using a hash and a name. For example:
<p vocab="http://schema.org/" about="#manu" typeof="Person">
My name is
<span property="name">Manu Sporny</span>
and you can give me a ring via
<span property="telephone">1-800-555-0199</span>.
<img property="image" src="http://manu.sporny.org/images/manu.png" />
</p>
If
we
assume
that
the
markup
above
can
be
found
at
http://example.org/people
,
then
the
identifier
for
the
thing
is
the
address,
plus
the
value
in
the
about
attribute.
Therefore,
the
identifier
for
the
thing
on
the
page
would
be:
http://example.org/people#manu
.
This
identifier
is
also
useful
if
you
want
to
talk
about
the
thing
on
another
Web
page.
By
identifying
all
things
on
the
Web
using
a
unique
Uniform
Resource
Locator
(URL),
we
can
start
building
a
Web
of
things.
Companies
building
software
for
the
Web
can
use
this
Web
of
things
to
answer
complex
questions
like:
"What
is
Manu
Sporny's
phone
number
and
what
does
he
look
like?".
The Working Group is considering replacing the @about attribute with @resource. The details of the proposal are outlined in the wiki . The Working Group needs feedback from Web authors and implementers in order to ensure that the decision reflects something that would be helpful to authors. This feature is considered "at risk" during the Last Call period. If we do not receive enough support for it, we will not replace @about with @resource. If we do receive enough support for the replacement, it will be replaced and the specification will continue to proceed to Candidate Recommendation status. The change would result in the example above being changed to the following:
<p vocab="http://schema.org/" resource="#manu" typeof="Person">
My name is
<span property="name">Manu Sporny</span>
and you can give me a ring via
<span property="telephone">1-800-555-0199</span>.
<img property="image" src="http://manu.sporny.org/images/manu.png" />
</p>
In some cases, a vocabulary may not have all of the terms an author needs when describing their thing . The last feature in RDFa 1.1 Lite that some authors might need is the ability to specify more than one vocabulary. For example, if we are describing a Person and we need to specify that they have a favorite animal, we could do something like the following:
<p vocab="http://schema.org/" prefix="ov: http://open.vocab.org/terms/" about="#manu" typeof="Person"> My name is <span property="name">Manu Sporny</span> and you can give me a ring via <span property="telephone">1-800-555-0199</span>. <img property="image" src="http://manu.sporny.org/images/manu.png" />My favorite animal is the <a >Liger</a>.My favorite animal is the <span property="ov:preferredAnimal">Liger</span>. </p>
The
example
assigns
a
short-hand
prefix
to
the
Open
Vocabulary
(
ov
)
and
uses
that
prefix
to
specify
the
preferredAnimal
vocabulary
term.
Since
schema.org
doesn't
have
a
clear
way
of
expressing
a
favorite
animal,
the
author
instead
depends
on
this
alternate
vocabulary
to
get
the
job
done.
RDFa
1.1
Lite
also
pre-defines
a
number
of
useful
and
popular
prefixes
,
such
as
dc
,
foaf
,
and
schema
.
This
ensures
that
even
if
authors
forget
to
declare
the
popular
prefixes,
that
their
structured
data
will
continue
to
work.
A
full
list
of
pre-declared
prefixes
can
be
found
in
the
initial
context
document
for
RDFa
1.1
.
If you would like to learn more about what is possible with RDFa Lite, including an introduction to the data model, please read the section on RDFa Lite in the RDFa Primer [ RDFA-PRIMER ].
As well as sections marked as non-normative, all authoring guidelines, diagrams, examples, and notes in this specification are non-normative. Everything else in this specification is normative.
The key words must , must not , required , should , should not , recommended , may , and optional in this specification are to be interpreted as described in [ RFC2119 ].
In
order
for
a
document
to
claim
that
it
is
be
labeled
as
a
conforming
HTML+RDFa
RDFa
Lite
document,
it
1.1
document
:
vocab
,
typeof
,
property
,
about
,
and
prefix
.
xmlns
attribute
is
not
used
to
declare
CURIE
prefixes.
A
User
Agent
is
considered
to
be
a
type
of
RDFa
Processor
when
the
User
Agent
stores
or
processes
RDFa
If
additional
non-RDFa
Lite
attributes
and
their
values.
The
reason
there
are
separate
used
from
the
RDFa
Processor
Conformance
and
a
User
Agent
Conformance
Core
1.1
specification,
the
document
must
sections
is
because
one
can
be
referred
to
as
a
valid
HTML5
conforming
RDFa
Processor
but
not
a
valid
HTML5
User
Agent
(for
example,
by
only
providing
a
very
small
subset
of
rendering
functionality).
The
User
Agent
conformance
criteria
are
listed
below,
all
of
which
are
mandatory:
A
User
Agent
must
1.1
document
.
All
conforming
RDFa
Lite
1.1
documents
may
conform
to
all
requirements
listed
in
the
Conformance
Requirements
section
of
the
HTML+RDFa
[
HTML-RDFA
]
specification
that
relate
be
referred
to
the
HTML5
language.
as
conforming
RDFa
1.1
documents.