For most of the '90s and the first part of this decade, content providers who wanted to publish online only needed to worry about the graphical web browser.

We found a way to make things look great to the human eye through the window of a graphical web browser without worrying about what everything looked like under the hood.

If I was designing a web site for elementary school children, I might have a much higher percentage of older computers with outdated browsers since keeping up with browser and hardware technology has not traditionally been a strong point of most elementary schools.

Because the competitive landscape of the web is such that the site which looks and works best gets the most traffic, developers and designers put a premium on the presentation of that content and let structural markup take a back seat.

Now that digital lifestyle devices, tablets, wireless phones, and other Internet appliances are beginning to come of age, we need to worry about presenting our content to these devices so that it is optimized for their display capabilities.

If you can use a Web browser, you can use Skype.