• by Mark Kecko  @scoopseven, April 2, 2002

If you’ve visited Yahoo! email or any of a few thousand pages elsewhere on the Internet recently, you’ve seen HTML frames in action. Much as their name implies, frames surround the content of a web page, and in the case of Yahoo! email, do so using a scrollbar in the middle and a menu on the left, so while the user is scrolling through the content the frame stays put, keeping other Yahoo! content accessible. On other sites, the same technology is used to separate the top of a page from the bottom, the left side from the right, and a multitude of other combinations. While frame technology may not seem revolutionary or even remotely exciting, it is the basis for another web design element called an inline frame—or I-Frame—which is significantly more useful for the purposes of this particular story.

As you can probably guess, I-Frames can and do serve ads, and while to the end user they look like regular graphics on a web page, the technology behind I-Frames makes them much more attractive to advertisers than a regular banner. Essentially an I-Frame appears as an image on the page. The host browser reserves space for the I-Frame just as it would for a banner, a skyscraper, a half-page or full-page ad, or another format, and while the host page is loading it requests the I-Frame contents from another web page, an ad server, or anywhere else on the Internet.

I-Frames can contain text, links, or any other HTML or rich media (Flash, etc.) element. They’re also scrollable (like their predecessors), so you can scroll through a document—or an entire web page—inside an I-Frame without scrolling the original page. But the best features of I-Frames are that (1) tracking displays and click-throughs is really easy, and (2) their technology allows advertisers to change their creative mid-campaign without sending new “tags.”

As with any new technology, there are some problems with I-Frames, one being fairly common—they don’t seem to work properly on Macintosh computers. There are also several reports of I-Frames’ not working properly with older browser versions, but an animated GIF banner tag, now appears between the starting and ending I-Frame tags, which ensures that compatible browsers see the I-Frame and incompatible ones see a GIF. If nothing else, I-Frames are more robust than Shockwave tags, which claim to be capable of such substitution but in reality very rarely work. Another turn-off is that most email systems don’t know what to do with an I-Frame. So while running a website campaign using I-Frames is relatively headache-free, an email campaign would be very problematic. Naturally, as HTML email becomes the norm and plain text the exception, email readers will be forced to deal with all HTML elements, including I-Frames.