As The Ultimate HTML Reference author Ian Lloyd puts it, “
blockquote has been around a long time, but it hasn’t aged a day.” But while the effect of the
<blockquote> tag in today’s browsers is virtually unchanged from when it was first introduced in the Web’s earliest browsers, the way we use it has progressed dramatically.
blockquote, of course, is meant to mark a “block quote”—a verbatim reproduction of content originally published or presented elsewhere, presented as a block, apart from the surrounding content. Belying this important purpose, the element’s default visual presentation is quite simple: browsers simply leave left and right margins of about 36 pixels to either side of the element.
Early on in the Web’s history,
blockquote was largely ignored. In a time when HTML elements were routinely misused to achieve visual effects,
blockquote was seen as the identical twin of
dd, since they both have the same visual effect, and because
<dd> is shorter to type than
<blockquote>, that’s what designers used.
Designers who took pride in the quality of their code quickly found HTML validators (like the W3C’s) didn’t appreciate them using
dd for this.
dd elements belong inside a definition list (
dl), after all. A
blockquote, on the other hand, can go anywhere a block element is welcome, so gradually it became the element of choice for producing indentend content.
The more indented a designer wanted content to appear, the more
blockquote elements he would wrap it in. This led to some pretty monstrous code, particularly when generated by WYSIWYG authoring tools:
<blockquote> <blockquote> <blockquote> <blockquote> <blockquote> <p>A block with a lot of breathing room!</p> </blockquote> </blockquote> </blockquote> </blockquote> </blockquote>
Of course, today most web designers understand the value of semantically meaningful code. This, and the fact that CSS can be used easily to apply the exact same formatting that
blockquote elements get by default, has seen correct use of
blockquote rise to dominate in recent years.
Meanwhile, the semantics provided by
blockquote are more relevant than ever. Blogs continually quote other blogs and sites, and the
blockquote element is perfectly suited to marking up such quotations.
Read on to discover some of the
blockquote element’s hidden subtleties, and how it could be used to reveal a web within the Web: a web of attribution.
A Web of Attribution
Many aspects of the Web are based on the concept of links. When I link to you in a blog post, Google counts that as a vote of confidence in your content. Modern blog software even “pings” the target of a link to let it know it has been linked to (this is called a trackback). So in many ways, the Web today is a web of links.
blockquote element has the potential to create a second “web within the Web”—a Web of attribution. This potential is created by the little-known
cite attribute, which is supposed to point to the URL from which the quote was taken.
<blockquote cite="http://example.com/source.html"> <p>A scintillating quote…</p> </blockquote>
If everyone marked up their
blockquotes this way, it would open the door to powerful analysis tools of the same sort that we now have for links. Not only would Google be able to tell you who links to you, but it could also tell you who was quoting you.
The problem with the
cite attribute, of course, is that almost nobody knows about it—and even fewer people use it! And the reason? In most browsers, it doesn’t do anything.
This is something that the Microformats community really gets—no matter how useful a feature of HTML would be to Google, developers won’t bother using it if that feature won’t be visible to the visitors to the site.
Microformats are ways of using existing features of the HTML language together to make the language do new things, and one of the rules of Microformats is that they are “defined for humans first and machines second.” The fact that a Microformat must be visible and useful to the site’s users gives designers a real reason to use it.
With this in mind, the Microformats community has proposed a way of using
blockquote to build a web of attribution in a user-visible way. The draft microformat is called cite-rel, and it looks like this:
<p> A scintillating quote from <cite id="goodquote" class="relationship"><a href="http://example.com/source.html" >someone I respect</a></cite>: </p> <blockquote cite="#goodquote"> <p>A scintillating quote…</p> </blockquote>
Instead of pointing directly at the source of the quote, the
cite attribute of the
blockquote points to the ID of a
cite element, which contains the actual link to the source.
Not only does this produce a structure that search engines can read to discover quotations and their sources on the Web, but it makes these citations visible to users, since the citation is ultimately presented in a link.
Next time you whip out a
blockquote, consider including a
cite attribute to point to the source, and even try out the cite-rel microformat to make that source visible to your users, not just Google!