The dfn element represents the defining instance of a term. The paragraph, description list group, or section that is the nearest ancestor of the dfn element must also contain the definition(s) for the term given by the dfn element.

• Defining term: If the dfn element has a title attribute, then the exact value of that attribute is the term being defined. Otherwise, if it contains exactly one element child node and no child text nodes, and that child element is an abbr element with a title attribute, then the exact value of that attribute is the term being defined. Otherwise, it is the exact textContent of the dfn element that gives the term being defined.

The abbr element represents an abbreviation or acronym, optionally with its expansion. The title attribute may be used to provide an expansion of the abbreviation. The attribute, if specified, must contain an expansion of the abbreviation, and nothing else.

The cite element represents the title of a work (e.g. a book, a paper, an essay, a poem, a score, a song, a script, a film, a TV show, a game, a sculpture, a painting, a theatre production, a play, an opera, a musical, an exhibition, a legal case report, etc). This can be a work that is being quoted or referenced in detail (i.e. a citation), or it can just be a work that is mentioned in passing.

• A person's name is not the title of a work — even if people call that person a piece of work — and the element must therefore not be used to mark up people's names. (In some cases, the b element might be appropriate for names; e.g. in a gossip article where the names of famous people are keywords rendered with a different style to draw attention to them. In other cases, if an element is really needed, the span element can be used.)

• <p>My favorite book is <cite>The Reality Dysfunction</cite> by
  Peter F. Hamilton. My favorite comic is <cite>Pearls Before
  Swine</cite> by Stephan Pastis. My favorite track is <cite>Jive
  Samba</cite> by the Cannonball Adderley Sextet.</p>
                  

• <p>According to <cite>the Wikipedia article on HTML</cite>, as it
  stood in mid-February 2008, leaving attribute values unquoted is
  unsafe. This is obviously an over-simplification.</p>
                  

  <p>According to the Wikipedia article <cite>HTML</cite>, as it
  stood in mid-February 2008, leaving attribute values unquoted is
  unsafe. This is obviously an over-simplification.</p>                

• <p><cite>Universal Declaration of Human Rights</cite>, United Nations,
  December 1948. Adopted by General Assembly resolution 217 A (III).</p>
                  

The q element represents some phrasing content quoted from another source.

• Quotation punctuation (such as quotation marks) that is quoting the contents of the element must not appear immediately before, after, or inside q elements; they will be inserted into the rendering by the user agent.

• <p>The W3C page <cite>About W3C</cite> says the W3C's
  mission is <q cite="http://www.w3.org/Consortium/">To lead the
  World Wide Web to its full potential by developing protocols and
  guidelines that ensure long-term growth for the Web</q>. I
  disagree with this mission.</p>
                  

The em element represents stress emphasis of its contents.

The strong element represents strong importance for its contents.

The i element represents a span of text in an alternate voice or mood, or otherwise offset from the normal prose in a manner indicating a different quality of text, such as a taxonomic designation, a technical term, an idiomatic phrase from another language, a thought, or a ship name in Western texts.

The b element represents a span of text to which attention is being drawn for utilitarian purposes without conveying any extra importance and with no implication of an alternate voice or mood, such as key words in a document abstract, product names in a review, actionable words in interactive text-driven software, or an article lede.

The u element represents a span of text with an unarticulated, though explicitly rendered, non-textual annotation, such as labeling the text as being a proper name in Chinese text (a Chinese proper name mark), or labeling the text as being misspelt.

• In most cases, another element is likely to be more appropriate: for marking stress emphasis, the em element should be used; for marking key words or phrases either the b element or the mark element should be used, depending on the context; for marking book titles, the cite element should be used; for labeling text with explicit textual annotations, the ruby element should be used; for labeling ship names in Western texts, the i element should be used.

The s element represents contents that are no longer accurate or no longer relevant.

• The s element is not appropriate when indicating document edits; to mark a span of text as having been removed from a document, use the del element.

• <p>Buy our Iced Tea and Lemonade!</p>
  <p><s>Recommended retail price: $3.99 per bottle</s></p>
  <p><strong>Now selling for just $2.99 a bottle!</strong></p>
  

The small element represents side comments such as small print.

• Small print typically features disclaimers, caveats, legal restrictions, or copyrights. Small print is also sometimes used for attribution, or for satisfying licensing requirements.
• The small element does not "de-emphasize" or lower the importance of text emphasized by the em element or marked as important with the strong element. To mark text as not emphasized or important, simply do not mark it up with the em or strong elements respectively.

The mark element represents a run of text in one document marked or highlighted for reference purposes, due to its relevance in another context. When used in a quotation or other block of text referred to from the prose, it indicates a highlight that was not originally present but which has been added to bring the reader's attention to a part of the text that might not have been considered important by the original author when the block was originally written, but which is now under previously unexpected scrutiny. When used in the main prose of a document, it indicates a part of the document that has been highlighted due to its likely relevance to the user's current activity.

• This example shows how the mark element can be used to bring attention to a particular part of a quotation:

  <p lang="en-US">Consider the following quote:</p>
  <blockquote lang="en-GB">
   <p>Look around and you will find, no-one's really
   <mark>colour</mark> blind.</p>
  </blockquote>
  <p lang="en-US">As we can tell from the <em>spelling</em> of the word,
  the person writing this quote is clearly not American.</p>
  

  (If the goal was to mark the element as misspelt, however, the u element, possibly with a class, would be more appropriate.)
• Another example of the mark element is highlighting parts of a document that are matching some search string. If someone looked at a document, and the server knew that the user was searching for the word "kitten", then the server might return the document with one paragraph modified as follows:

  <p>I also have some <mark>kitten</mark>s who are visiting me
  these days. They're really cute. I think they like my garden! Maybe I
  should adopt a <mark>kitten</mark>.</p>
  

• In the following snippet, a paragraph of text refers to a specific part of a code fragment.

  <p>The highlighted part below is where the error lies:</p>
  <pre><code>var i: Integer;
  begin
     i := <mark>1.1</mark>;
  end.</code></pre>
  

  This is separate from syntax highlighting.

The code element represents a fragment of computer code. This could be an XML element name, a filename, a computer program, or any other string that a computer would recognize.

• Although there is no formal way to indicate the language of computer code being marked up, authors who wish to mark code elements with the language used, e.g. so that syntax highlighting scripts can use the right rules, may do so by adding a class prefixed with "language-" to the element.

  <pre><code class="language-pascal">var i: Integer;
  begin
     i := 1;
  end.</code></pre>
  <p>The <code>code</code> element represents a fragment of computer
  code.</p>
          

The samp element represents (sample) output from a program or computing system.

• <p>The computer said <samp>Too much cheese in tray
  two</samp> but I didn't know what that meant.</p>
          

• <pre><samp><span class="prompt">jdoe@mowmow:~$</span> <kbd>ssh demo.example.com</kbd>
  Last login: Tue Apr 12 09:10:17 2005 from mowmow.example.com on pts/1
  Linux demo 2.6.10-grsec+gg3+e+fhs6b+nfs+gr0501+++p3+c4a+gr2b-reslog-v6.189 #1 SMP Tue Feb 1 11:22:36 PST 2005 i686 unknown
  
  <span class="prompt">jdoe@demo:~$</span> <span class="cursor">_</span></samp></pre>
          

The kbd element represents user input (typically keyboard input, although it may also be used to represent other input, such as voice commands).

• When the kbd element is nested inside a samp element, it represents the input as it was echoed by the system.
• When the kbd element contains a samp element, it represents input based on system output, for example invoking a menu item.

  <p>To make George eat an apple, select
      <kbd><kbd><samp>File</samp></kbd>|<kbd><samp>Eat Apple...</samp></kbd></kbd>
  </p>
          

  Such precision isn't necessary; the following is equally fine:

  <p>To make George eat an apple, select <kbd>File | Eat Apple...</kbd></p>
          

• When the kbd element is nested inside another kbd element, it represents an actual key or other single unit of input as appropriate for the input mechanism.

  <p>To make George eat an apple, press <kbd><kbd>Shift</kbd>+<kbd>F3</kbd></kbd></p>
          

The var element represents a variable. This could be an actual variable in a mathematical expression or programming context, or it could just be a term used as a placeholder in prose.

The sup element represents a superscript and the sub element represents a subscript.

• These elements must be used only to mark up typographical conventions with specific meanings, not for typographical presentation for presentation's sake. For example, it would be inappropriate for the sub and sup elements to be used in the name of the LaTeX document preparation system. In general, authors should use these elements only if the absence of those elements would change the meaning of the content.
• Here, the sub element is used to represents the subscript that identifies the variable in a family of variables:

  <p>The coordinate of the <var>i</var>th point is
  (<var>x<sub><var>i</var></sub></var>, <var>y<sub><var>i</var></sub></var>).
  For example, the 10th point has coordinate
  (<var>x<sub>10</sub></var>, <var>y<sub>10</sub></var>).</p>
                  

• Mathematical expressions often use subscripts and superscripts. Authors are encouraged to use MathML for marking up mathematics, but authors may opt to use sub and sup if detailed mathematical markup is not desired.

  <var>E</var>=<var>m</var><var>c</var><sup>2</sup>
  f(<var>x</var>, <var>n</var>) = log<sub>4</sub><var>x</var><sup><var>n</var></sup>
                  

The bdi element represents a span of text that is to be isolated from its surroundings for the purposes of bidirectional text formatting.

• The dir global attribute defaults to auto on this element (it never inherits from the parent element like with other elements).
• For the purposes of applying the bidirectional algorithm to the contents of a bdi element, user agents must treat the element as a paragraph-level container. For the purposes of applying the bidirectional algorithm to the paragraph-level container that a bdi element finds itself within, the bdi element must be treated like a U+FFFC OBJECT REPLACEMENT CHARACTER (in the same manner that an image or other inline object is handled).

The bdo element represents explicit text directionality formatting control for its children. It allows authors to override the Unicode bidirectional algorithm by explicitly specifying a direction override.

• Authors must specify the dir attribute on this element, with the value ltr to specify a left-to-right override and with the value rtl to specify a right-to-left override.

The br element represents a line break.

• br elements must be used only for line breaks that are actually part of the content, as in poems or addresses.

The wbr element represents a line break opportunity.

• So then he pointed at the tiger and screamed
  "thereisnowayyouareevergoingtocatchme"!
          

Usage summary

Visit my <a href="drinks.html">drinks</a> page.

I must say I <em>adore</em> lemonade.

This tea is <strong>very hot</strong>.

These grapes are made into wine. <small>Alcohol is addictive.</small>

Price: <s>£4.50</s> £2.00!

The case <cite>Hugo v. Danielle</cite> is relevant here.

The judge said <q>You can drink water from the fish tank</q> but advised against it.

The term <dfn>organic food</dfn> refers to food produced without synthetic chemicals.

Organic food in Ireland is certified by the <abbr title="Irish Organic Farmers and Growers Association">IOFGA</abbr>.

Published <time>2009-10-21</time>.

The <code>fruitdb</code> program can be used for tracking fruit production.

If there are <var>n</var> fruit in the bowl, at least <var>n</var>÷2 will be ripe.

The computer said <samp>Unknown error -3</samp>.

Hit <kbd>F1</kbd> to continue.

Water is H<sub>2</sub>O.

The Hydrogen in heavy water is usually <sup>2</sup>H.

Lemonade consists primarily of <i>Citrus limon</i>.

Take a <b>lemon</b> and squeeze it with a <b>juicer</b>.

The mixture of apple juice and <u class="spelling">eldeflower</u> juice is very pleasant.

Elderflower cordial, with one <mark>part</mark> cordial to ten <mark>part</mark>s water, stands a<mark>part</mark> from the rest.

<ruby> OJ <rp>(<rt>Orange Juice<rp>)</ruby>

The recommended restaurant is <bdi lang="">My Juice Café (At The Beach)</bdi>.

The proposal is to write English, but in reverse order. "Juice" would become "<bdo dir=rtl>Juice</bdo>"

In French we call it <span lang="fr">sirop de sureau</span>.

Simply Orange Juice Company<br>Apopka, FL 32703<br>U.S.A.

www.simply<wbr>orange<wbr>juice.com