Jan 3 2011

Structural Tags in HTML5

The HTML5 specification has added quite a few interesting and useful tags for structuring your markup. For a majority of everyday uses, these tags will replace many of our typical div entries from our code. So let’s dig in.

Defining Structure

<section>

A section is a thematic grouping of content, typically preceded by header, possibly with a footer after. sections can be nested inside of each other, if needed, and can hold any amount of typical markup.

<header>

The header of a section, typically a headline or grouping of headlines, but may also contain supplemental information about the section.

<footer>

A footer typically contains information about its section such as who wrote it, links to related documents, copyright data, and the like.

<nav>

Defines the navigation area, typically a list of links. The nav should be a sibling of the main section, header, and footer.

<article>

An independent entry in a blog, magazine, compendium, and so on.

<aside>

An aside indicates content that is tangentially related to the content around it.

Putting it Together

So let’s take a look at how we would put together a typical blog page with our new structural tags.

<!DOCTYPE html>
<html>
  <head>
    <title>Standard Blog</title>
  </head>
  <body>
    <header>
      <h1><a href="#">Standard Blog</a></h1>
    </header>
    <nav>
      <ul>
        <li><a href="#">Home</a></li>
        <li><a href="#">Archives</a></li>
        <li><a href="#">About</a></li>
        <li><a href="#">Contact</a></li>
      </ul>
    </nav>
    <section>
      <article>
        <header>
          <h1><a href="#">Title</a></h1>
        </header>
        <section>
          <p>Lorem ipsum...</p>
        </section>
      </article>
      <article>
        <header>
          <h1><a href="#">Title</a></h1>
        </header>
        <section>
          <p>Lorem ipsum...</p>
        </section>
      </article>
      <article>
        <header>
          <h1><a href="#">Title</a></h1>
        </header>
        <section>
          <p>Lorem ipsum...</p>
        </section>
      </article>
    </section>
    <footer>
      <p>Copyright © 2008 All Rights</p>
    </footer>
  </body>
</html>

Note: This example is a little verbose in markup for the simplicity of the content, but I wanted to exaggerate for emphasis.

As you can see, the tags themselves are much more descriptive than simply providing an id attribute to a div. This also gives the added benefit of a descriptive closing tag, as </article> is much more understandable that wondering which <div id="something"> goes with a given </div>.

So, I can use this now?

Actually, yes, with a few extra steps. And it will work in all modern browsers. It can even work in IE6. There are only a few little quirks we need to get past if we’re going to start using this today.

First, because most browsers don’t understand the new HTML5 doctype, they don’t know about these new tags in HTML5. Fortunately, due to the flexibility of browsers, they deal well with unknown tags. The only issue here is unknown tags have no default style, and are treated as inline tags. These new HTML5 tags are structural, and should obviously be block level elements. So, when we style them with CSS, we need to be sure to include display:block; in our attribute/value pairs.

Include this simple extra piece of CSS, and these new tags are immediately usable. Starting today. And of course, once HTML5 is more widely supported, the superfluous display:block; can be removed, as it will be included in the browser default styles.

Supporting IE

There is one more issue if you require IE support. Turns out that the IE rendering engine will work with the new tags, but will not recognize any CSS applied to them. Well, that’s no good. Fortunately, IE just needs a good swift kick with the help of a very simple bit of JavaScript. All we need to do to kick start IE is to create a DOM node with JavaScript for each of the new tags, and suddenly IE will apply styles to the new tags with no problem. The code will look something like this, and can be placed directly in the head of our document, or the contents of the script tag placed into an external file and included.

<script>
  document.createElement('header');
  document.createElement('footer');
  document.createElement('section');
  document.createElement('aside');
  document.createElement('nav');
  document.createElement('article');
</script>

Before we leave this code, there’s one thing to mention about the script tag in HTML5. HTML5 will assume type="text/javascript" on any script element, so it need not be included. Once again, making things simple.

Wrapping Up

So we can begin, right now, to structure our documents using the new tags provided in HTML5. With a few simple tricks, they’ll work today, and be compatible in the future. So next time you start a new site, consider going with HTML5, and give your markup a little more defined structure.