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    <p>That's the regular italics tag, but without any contents; i.e. it's <em>semantically</em> equivalent to <code>&lt;i&gt;&lt;/i&gt;</code>.<sup>&dagger;</sup></p> <p>In <a href="http://www.w3.org/TR/REC-xml/" rel="nofollow noreferrer">XML</a>, empty elements are written with an extra slash at the end. <a href="http://www.w3.org/TR/xhtml1/" rel="nofollow noreferrer">XHTML</a> is valid XML. So <code>&lt;i/&gt;</code> is fine. For a more common example, think of e.g. <code>&lt;br /&gt;</code>.</p> <p>To see for yourself that <code>&lt;i/&gt;</code> is a valid XHTML tag, check the <a href="http://www.w3.org/TR/REC-xml/#d0e2480" rel="nofollow noreferrer">XML <code>EmptyElemTag</code> definition</a> or pass the following to the <a href="http://validator.w3.org/" rel="nofollow noreferrer">W3C validator</a>:</p> <pre><code>&lt;!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"&gt; &lt;html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"&gt; &lt;head&gt; &lt;title&gt;&lt;/title&gt; &lt;/head&gt; &lt;body&gt; &lt;p&gt;&lt;i/&gt;&lt;/p&gt; &lt;!-- look here --&gt; &lt;/body&gt; &lt;/html&gt; </code></pre> <hr> <p>&nbsp;&nbsp;<sup>&dagger;</sup> As <a href="https://stackoverflow.com/users/25968/toji">Toji</a> correctly points out, the <em>syntactic</em> difference is relevant under certain circumstances. Though browsers may not treat <code>&lt;i/&gt;</code> any different from <code>&lt;i&gt;&lt;/i&gt;</code>, other XML parsers could!</p>
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    1. POJust noticed the `<i/>` tag on Twitter, did they make that up?
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    1. POJust noticed the `<i/>` tag on Twitter, did they make that up?
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    1. CONo, it's not equivalent! In many cases they will be treated the same, so the are *functionally* equivalent most of the time. Any decent XML parser will allow you to detect the difference between empty elements (<tag/>) and elements with 0 length content (<tag></tag>), at which point the implementation may treat them differently. Simply because most don't does not indicate that they are the same. Sorry to rant a bit about a technicality, but the distinction should be made!
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    2. CO@Toji: you are very right to point out the distinction between syntactic and semantic equivalence. I'll update the answer to reflect this.
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    3. COActually, there's nothing in the XML spec that says these two constructs are different: <tag/> and <tag></tag>. In fact, in the Annotated XML Spec (http://www.xml.com/axml/testaxml.htm), Tim Bray says, "So, is this: <img src='madonna.gif'></img> really exactly the same as <img src='madonna.gif'/>? As far as XML is concerned, they are." If an XML parser lets you see the distinction, it's similar to it letting you know whether an attribute was enclosed in single-quotes vs. double-quotes. It isn't a distinction, it's trivia.
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A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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