HTML and CSS Reference
In-Depth Information
The different content types aren't applied arbitrarily; each has a dis-
tinct meaning. The following table summarizes the different types.
Most elements are categorized as flow content. It's the default content
type for elements visible on the page.
Flow content
Sectioning content defines the scope of headers and footers and feeds
into the document outline.
Sectioning content
Heading content
Heading content, as you might expect, is just for headings and
<hgroup>
.
Phrasing content is mostly used to describe the text of a document. In
most cases, phrasing content can only contain other phrasing content.
Phrasing content
Embedded content is used to put an external resource into the web
page—for example, an image or video.
Embedded content
Interactive content is elements that are specifically intended for user inter-
action—mostly form controls. Note that other elements can be made
responsive to user input through the use of JavaScript, but elements cate-
gorized as interactive content have default functionality in the browser.
Interactive content
Metadata content sets up the presentation or behavior of the rest of the
content, or sets up the relationship of the document with other documents,
or conveys other out-of-band information.
Metadata content
Now that you know all about the content model, you'll be able to use
the
HTML5
spec to write valid
HTML5
documents. That's more than
enough theory for now. The next section gets back to practicalities and
considers whether your users' browsers will support
HTML5
and what
to do about it if they don't.
Browser support
Do the new elements we've discussed in this chapter work in today's
browsers? The short answer is, yes (with a couple of exceptions); the
For a text element like
<p>
, which isn't required to do much except appear on
the page, there are two principal requirements:
It shows up in the DOM with at least a standard set of element properties.
❂
It shows up in the user's browser with some sort of default presentation.
❂
