RISC DISC 2/RISC_DISC_2.iso/the_web/documents/spec/html_spec/phrase_sgm

Text File | 1995-06-15 | 8.0 KB | 259 lines

<h2>Phrase Markup

<p>Phrases may be marked up according to idiomatic usage,
typographic appearance, or for use as hyperlink anchors.

<p>User agents must render highlighted phrases distinctly from plain
text. Additionally, <tag/EM/ content must be rendered as distinct from
<tag/STRONG/ content, and <tag/B/ content must rendered as distinct
from <tag/I/ content.

<p>Phrase elements may be nested within the content of other phrase
elements; however, HTML user agents may render nested phrase
elements indistinctly from non-nested elements:

<listing><![CDATA[
plain <B>bold <I>italic</I></B> may be rendered
the same as plain <B>bold </B><I>italic</I>
]]></listing>

<h3>Idiomatic Elements

Phrases may be marked up to indicate certain idioms.
<note>
User agents may support the <tag/DFN/ element, not
included in this specification, as it has been deployed to some extent.
It is used to indicate the defining instance of a term, and it is
typically rendered in italic or bold italic.
</note>

<h4>Citation: CITE

<p>The <tag/CITE/ element is used to indicate the title of a book or
other citation. It is typically rendered as italics.  For example:

<listing><![CDATA[
He just couldn't get enough of <cite>The Grapes of Wrath</cite>.
]]></listing>

<h4>Code: CODE

<p>The <tag/CODE/ element indicates an example of code, typically
rendered in a mono-spaced font. The <tag/CODE/ element is intended
for short words or phrases of code; the <tag/PRE/ block
structuring element (<hdref refid=pre>) is more apropriate for
multiple-line listings. For example:

<listing><![CDATA[
The expression <code>x += 1</code>
is short for <code>x = x + 1</code>.
]]></listing>

<h4>Emphasis: EM

<p>The <tag/EM/ element indicates an emphasized phrase, typically
rendered as italics. For example:

<listing><![CDATA[
A singular subject <em>always</em> takes a singular verb.
]]></listing>

<h4>Keyboard: KBD

<p>The <tag/KBD/ element indicates text typed by a user, typically
rendered in a mono-spaced font. This is commonly used in instruction
manuals. For example:

<listing><![CDATA[
Enter <kbd>FIND IT</kbd> to search the database.
]]></listing>

<h4>Sample: SAMP

<p>The <tag/SAMP/ element indicates a sequence of literal characters,
typically rendered in a mono-spaced font. For example:

<listing><![CDATA[
The only word containing the letters <samp>mt</samp> is dreamt.
]]></listing>

<h4>Strong Emphasis: STRONG

<p>The <tag/STRONG/ element indicates strong emphasis,
typically rendered in bold. For example:

<listing><![CDATA[
<strong>STOP</strong>, or I'll say "<strong>STOP</strong>" again!.
]]></listing>

<h4>Variable: VAR

<p>The <tag/VAR/ element indicates a placeholder variable, typically rendered
as italic. For example:

<listing><![CDATA[
Type <SAMP>html-check <VAR>file</VAR> | more</SAMP>
to check <VAR>file</VAR> for markup errors.
]]></listing>

<h3>Typographic Elements

<p>Typographic elements are used to specify the format of marked text.

<p>Typical renderings for idiomatic elements may vary between user
agents. If a specific rendering is necessary — for example, when
referring to a specific text attribute as in "The italic parts are
mandatory" — a typographic element can be used to ensure that the
intended typography is used where possible.

<note>
User agents may support some typographic elements not included in
this specification, as they have been deployed to some extent. The
<tag/STRIKE/ element indicates horizontal line through the characters,
and the <tag/U/ element indicates an underline.
</note>

<h4>Bold: B

<p>The <tag/B/ element indicates bold text. Where bold typography is
unavailable, an alternative representation may be used.

<h4>Italic: I

<p>The <tag/I/ element indicates italic text. Where italic typography
is unavailable, an alternative representation may be used.

<h4>Teletype: TT

<p>The <tag/TT/ element indicates teletype (monospaced )text. Where a
teletype font is unavailable, an alternative representation may be
used.

<h3 id=a>Anchor: A

<p>The <tag/A/ element indicates a hyperlink anchor (see <hdref
refid=hyperlink>). At least one of the <attr/NAME/ and <attr/HREF/
attributes should be present. Attributes of the <tag/A/ element:

<tl>
<tli>HREF: gives the URI of the head anchor of a hyperlink.

<tli>NAME: gives the name of the anchor, and makes it available as
a head of a hyperlink.

<tli>TITLE: suggests a title for the destination resource —
advisory only.  The <attr/TITLE/ attribute may be used:

<ul>
<li> for display prior to accessing the destination resource, for
example, as a margin note or on a small box while the mouse is over
the anchor, or while the document is being loaded;

<li> for resources that do not include a title, such as graphics, plain
text and Gopher menus, for use as a window title.
</ul>

<tli>REL: The <attr/REL/ attribute gives the relationship(s) described
by the hyperlink. The value is a whitespace separated list of
relationship names.

<tli>REV: same as the REL attribute, but the semantics of the
relationship are in the reverse direction. A link from A to B with
REL="X" expresses the same relationship as a link from B to A with
REV="X". An anchor may have both REL and REV attributes.

<tli>URN: specifies a preferred, more persistent identifier for the
head anchor of the hyperlink. The syntax and semantics of the
<attr/URN/ attribute are not yet specified.

<tli>METHODS: specifies methods to be used in accessing the
destination, as a whitespace-separated list of names. The set of
applicable names is a function of the scheme of the URI in the
<attr/HREF/ attribute. For similar reasons as for the TITLE attribute,
it may be useful to include the information in advance in the
link. For example, the HTML user agent may chose a different rendering
as a function of the methods allowed; for example, something that is
searchable may get a different icon.
</tl>

<h2>Line Break: BR

<p>The <tag/BR/ element specifies a line break between words (see
<hdref refid=datachrs>). For example:

<listing><![CDATA[
<P> Pease porridge hot<BR>
Pease porridge cold<BR>
Pease porridge in the pot<BR>
Nine days old.
]]></listing>

<h2>Horizontal Rule: HR

<p>The <tag/HR/ element is a divider between sections of text;
typically a full width horizontal rule or equivalent graphic. For
example:

<listing><![CDATA[
<HR>
<ADDRESS>February 8, 1995, CERN</ADDRESS>
</BODY>
]]></listing>

<h2 id=img>Image: IMG

<p>The <tag/IMG/ element refers to an image or icon via a hyperlink
(see <hdref refid=image-present>).

<p>HTML user agents may process the value of the <attr/ALT/ attribute
as an alternative to processing the image resource indicated by the
<attr/SRC/ attribute.
<note>Some HTML user agents can process graphics linked via anchors,
but not <tag/IMG/ graphics. If a graphic is essential, it should be
referenced from an <tag/A/ element rather than an <tag/IMG/ element. If
the graphic is not essential, then the <tag/IMG/ element is
appropriate.
</note>

<p>Attributes of the <tag/IMG/ element:

<tl>
<tli>ALIGN: alignment of the image with respect to the text
baseline.
<ul>
<li><code/TOP/ specifies that the top of the image aligns with the
tallest item on the line containing the image.

<li><code/MIDDLE/ specifies that the center of the image aligns with
the baseline of the line containing the image.

<li><code/BOTTOM/ specifies that the bottom of the image aligns with
the baseline of the line containing the image.
</ul>

<tli>ALT: text to use in place of the referenced image resource, for
example due to processing constraints or user preference.

<tli>ISMAP: indicates an image map (see <hdref refid=imagemap>).

<tli>SRC: specifies the URI of the image resource.
<note>In practice, the media types of image resources are limited to a
few raster graphic formats: typically <code>image/gif</code>,
<code>image/jpeg</code>. In particular, <code>text/html</code>
resources are not intended to be used as image resources.
</note>
</tl>

<p>Examples of use:

<listing><![CDATA[
<IMG SRC="triangle.xbm" ALT="Warning:"> Be sure
to read these instructions.
]]></listing>

<listing><![CDATA[
<a href="http://machine/htbin/imagemap/sample">
<IMG SRC="sample.xbm" ISMAP>
</a>
]]></listing>