HTML and CSS Reference
In-Depth Information
Relationship
Value
Explanation
Example
Notes
This value specifies
a URL that should be
displayed in a browser
sidebar.
Assumes that
browsers support
this interface
style.
sidebar
<a href="instructions
.html"
rel="sidebar">
Load Instructions
(Sidebar)
</a>
This value specfies a
tag that applies to the
document.
Specification
unclear on usage.
Current read
suggests tag
word used within
“tagcloud.”
tag
<a href="html5.html"
rel="tag">
HTML5
</a>
up
This value provides
a link to a document
or section “up” from
the current document,
usually the parent or
index document for the
current URL.
<a href="/main/index.html"
rel="up">
Index Page
</a>
T
ABLE
3-8 Possible rel Values (continued)
target
This attribute specifies the target window for a hypertext source link that references
frames. The information linked to
target
will be displayed in the named window. Frames
and windows must be named to be targeted if they do not correspond to a special name
value, which include
_blank
, which indicates a new window;
_parent
, which indicates the
parent frame set containing the source link;
_self
, which indicates the frame containing the
source link; and
_top
, which indicates the full browser window.
type
This attribute specifies the media type in the form of a MIME type for the link target.
Generally, this is provided strictly as advisory information; however, in the future a browser
might add a small icon for multimedia types. For example, a browser might add a small
speaker icon when
type
is set to
audio/wav
. For a complete list of recognized MIME types,
see www.w3.org/TR/html4/references.html#ref-MIMETYPES.
urn
This supposedly Internet Explorer-supported attribute has some origins in HTML 3.2
and it relates a uniform resource name (URN) with the link. While it is based on standards
work going years back, the meaning of URNs is still not well defined nor has it been
demonstrated that this attribute does anything despite its occurrence in MSDN
documentation.
