HTML & XHTML: The Definitive Guide, 5th Edition

Using XML

Our address example is trivial. It hardly scratches the surface of the wide range of applications that XML is suited for. To whet your appetite, here are some common uses for XML that you will certainly be seeing now and in the future.

Creating Your Own Markup Language

We touched on this earlier when we mentioned that the latest versions of HTML are being reformulated as compliant XML DTDs. We cover the impact XML has on HTML in the next chapter.

But even more significantly, XML enables communities of users to create languages that best capture their unique data and ideas. Mathematicians, chemists, musicians, and professionals from hundreds of other disciplines can create special tags that represent unique concepts in a standardized way. Even if no browser exists that can accurately render these tags in a displayable form, the ability to capture and standardize information is tremendously important for future extraction and interpretation of these ideas.

For more mainstream XML applications with established audiences, it is easy to envision custom browsers being created to appropriately display the information. Smaller applications or markets may have more of a challenge creating markup languages that enjoy such wide acceptance. Creating the custom display tool for a markup language is difficult; delivering that tool for multiple platforms is expensive. As we’ve noted, some of these display concerns can be mitigated by appropriate use of style sheets. Luckily, XML’s capabilities ...