Creating Floating Frames

Microsoft introduced the concept of a floating frame with Internet Explorer 3. You can think of a floating frame as a smaller browser window that you can open in your main browser window—much like the picture-in-picture feature that comes with many television sets. The same as with regular frames, you can load any XHTML document you want into a floating frame. The primary difference is that floating frames can be placed anywhere on a page that you can place an image. In fact, you'll find the XHTML syntax for placing floating frames to be similar to that for placing an image.

You place a floating frame on a page by using the <iframe> element. A browser that can do floating frames ignores anything within this element, enabling you to place an alternative to the floating frame (most likely text or an image) on the page as well. This way, browsers that don't know how to render floating frames can ignore the <iframe> element and act on what is found inside it. The <iframe> element can take the attributes summarized in Table 7.2.