All About: eXtensible Markup Language, XML

2005-05-25

XML has its roots in formatting languages used for document layout, typesetting and production. It is said that the languages were too complex, and a simpler version was developed. XML’s strength lies in its simplicity – it provides a basis to define all forms of digital data, from simple text and values to voice transmissions, multimedia and 3-dimensional graphics. XML provides a basis for systems to interact and to exchange data of any form. If the Internet is the global network, so XML is fast becoming the global language for information interchange.

Here we describe XML both from a technical and a managerial standpoint. We look at the ways a business can benefit from XML, and how XML-based facilities can be deployed. We consider the downsides of XML and look at how it is likely to ex=volve both as a language and as a movement.

What is XML? The eXtensible Markup Language (XML) is a language for representing data. Quite simple, really. It looks a little like HTML, in that it uses tags (like ) to structure and format the data. It is simpler than HTML in that it does not define specific tags, but it is more complex in that it requires the tags to be defined. The simplicity of XML is its strength. It can be used for everything from legal documents to comic strips (articles have quite rightly coined XML “The Tupperware of the Internet”).

The Business Benefits of XML Clearly, as XML is just a language it has many potential uses. Its strength lies in its standardisation – if more than one party agrees to use XML (and, what is more, agrees on the format of XML to be used), then the two parties can communicate. XML also overcomes many of the limitations of HTML.

Three application areas are exploiting this strength, each with its own benefits to business: these are content management, business-to-business (B2B) e-commerce and Web services.

• Content Management. • B2B E-Commerce • Web Services • Business re-engineering.

Issues with XML What could possibly be wrong with XML? After all, it is just a formatting language. The answer lies in Bananarama’s first law of IT – “It’s not what you do it’s the way that you do it”: the risks with XML are not so much with the language itself, rather in how it is used. If nothing else, remember the adage “real programmers can write FORTRAN in any language.”

There is an industry fear that “simple” XML will become SGML as new capabilities and features are added to the language to support more complex constructions and data types. However most of us will not care, as long as the message gets passed. XML is only the messenger.