HTML & XHTML: The Definitive Guide, 6th Edition

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 different way to reference images, along with audio, video, and other document formats.

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 externally—particularly large ones in which details are important but not immediately necessary to the document content. Other multimedia elements, including digital audio and video, can be referenced as separate documents external to the current one.

You normally use the anchor tag (<a>) to link external multimedia elements 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 document 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 ...