HTML and CSS Reference
In-Depth Information
5.6. Other Multimedia Content
The Web is completely open-minded about the types of content that can
be exchanged by servers and browsers. In this section, we look at a dif-
ferent way to reference images, along with audio, video, and other doc-
ument formats.
5.6.1. Embedded Versus Referenced Content
Images currently enjoy a special status among the various media that
can be included within an HTML or XHTML document and displayed inline
with other content by all but a few browsers. Sometimes, however, as we
discussed earlier in this chapter, you may also reference images extern-
allyparticularly large ones in which details are important but not imme-
diately necessary to the document content. Other multimedia elements,
including digital audio and video, can be referenced as separate docu-
ments external to the current one.
You normally use the anchor tag (
<a>
) to link external multimedia ele-
ments to the current document. Just like other link elements selected by
the user, the browser downloads the multimedia object and presents it to
the user, possibly with the assistance of an external application or plug-
in. Referenced content is always a two-step process: present the docu-
ment that links to the desired multimedia object, then present the object
if the user selects the link. [
<a>, 6.3.1
]
In the case of images, you can choose how to present images to the
user: inline and immediately available via the
<img>
tag, or referenced
and subsequently available via the
<a>
tag. If your images are small and
critical to the current document, you should provide them inline. If they
are large or are only a secondary element of the current document, make
them available as referenced content via the
<a>
tag.
If you choose to provide images via the
<a>
tag, it is sometimes a cour-
tesy to your readers to indicate the size of the referenced image in the
referencing document and perhaps provide a thumbnail sketch. Users can
then determine whether it is worth their time and expense to retrieve it.
