Summary:XML technology enables a host of new web techniques which enable B2B applications, RSS web feeds, and AJAX client side interactive web experiences. Collectively, these modern web techniques provide a more rewarding user experience and promote a closer engagement with the customer. XML and its related languages and envelopes will likely continue to be exploited to even greater effect in the web communication between buyers and sellers, vendors and clients. This article is intended to describe the functionality of that technology, and to suggest ways that users might be able to employ techniques enables by XML to grow their business and better engage and serve their customers. Chitrangana, India has in depth experience in the construction and implementation of this and similar techniques.

XML (eXtensible Markup Language) is a very important and key technology in today’s internet, and other applications involved in the smooth transfer of data between computers. As a markup language, it bears a family resemblance to other similarly named languages, most notably HTML or HyperText Markup Language. HTML is the language of the internet which allows web pages to be displayed and formatted in multiple browser configurations with the two-fold objectives of flexible formatting (to allow layouts to be presented adequately across multiple screen sizes), and the enabling of hypertext, or the links which allow the user to ‘jump’ to other related pages with the click of a mouse.

The operative genetic link between these two languages is the ‘Markup Language’ common component of their names. The markup language means that content of the files using these languages are enclosed in ‘tags’ or labels, which define their context. But there the similarity ends. HTML recognizes a list of perhaps 200 words that when properly used as labels and descriptors can allow a web page to be rendered or interpreted into what passes as a well formatted document.

XML, on the other hand doesn’t DO anything. It provides the mechanism to store reasonable amounts of data in a commonly accepted and defined format for transfer and communication between computers and systems. Its vocabulary is theoretically unlimited in that tags may be made up and transmitted at will,provided that their punctuation is proper. The files themselves are made up of elements which are delimited by these tags. XML tags are case sensitive, whereas HTML tags are not. The elements, or nodes may be multi-generational with some elements having lesser nodes describing characteristics or individuals of the larger nodes. Here’s an example of a small XML document which simulates a group of appointment book entries:

<?xml version=”1.0″ ?>

<appointmentplanner>

- <year value=”2010“>
- <date month=”4“ day=”15“>
<note time=”1230“>Doctor’s appointment</note>
<note time=”1420“>C# Class</note>
</date>
- <date month=”4“ day=”17“>
<note>Easter</note>
</date>
- <date month=”4“ day=”20“>
<note time=”0900“>Network Configuration Mtg</note>
</date>
- <date month=”4“ day=”20“>
<note time=”2100“>Party at Joe’s</note>
</date>
- <date month=”4“ day=”23“>
<note time=”1400“>Budget Presentation</note>
</date>
</year>
</appointmentplanner>

XML is truly an abstract language. There are no specific words required, only that each element, including the root element of the document itself, be enclosed by matching tags, and that its first line declare that it is an XML document.

There’s more. One can actually create an XML language which will act as a container for a specific application. This involves an additional referenced file which contains those definitions. These files are called schemas or DTD documents (Data Type Definition) which can actually define the permitted or required elements in an XML file. One could invent an XML application language which would be specific to -say– chemistry (requiring definition of atomic numbers, or isotope variants), or medicine (perhaps a separate schema for each specialty, or even for each doctor within a practice) The schemas or DTDs can define the type of data within an element – text, video, binary, file, or whatever. This is very powerful technology.

There are several ancillary technologies related to XML which magnify its strengths. For instance XPATH and XQUERY empower the user to parse an XML document to extract portions or elements of the document related to what he is seeking – much like Regular Expression and database query technologies. XSLT uses the XPATH functionality to format an XML document. And there is facility within modern day relational databases to receive data from XML, and deliver data from XML, distributing and gathering it appropriately from relational tables.

The flexibility and abstract nature of XML make the protocol extremely adaptable and useful for exchanging all manner of data between applications.

Business to Business transactions are now typically (orders, confirmations, quotes) transacted using XML, or one of its variants or extensions. This allows a buyer company using Windows machines to communicate and accept confirmation of orders to their supplier company who is running a Unix system
RSS transmissions are standardized using XML, or its close cousin ATOM protocols. This allows a light weight individually tailored package to be delivered to the user and interpreted successfully, whether the user is a Mac Windows, or Linux machine.
XML allows websites to provide a web page to be displayed and tailored to each individual. This is more complex than Amazon’s personal recommendations. This technique is closer to the iGoogle page which allow you to construct your own home page. The preferences and URLs you ask for, are formatted to the way you set them, then stored in an XML file.
XML technology would allow you to construct a feed of your Twitter or Product Specials information to be constantly updated on your blog or website.
AJAX (asynchronous Javascript and XML) techniques which use XML with javascriptis a technique which allows an interactive and dynamic web experience for the user by empowering the client side web application to update the web page depending on choices made real time by the user.
The best thing about these interactions is that they are done under the radar. There is no need to take any action either as sender or receiver of this information, since the XML filesare created and interpreted without any human interaction. This is a very easy to provide updated fresh content for a website or blog without expending additional resources. XML is related to and is basic to similar protocols like SOAP (Simple Object Access Protocol) and JSON (JavaScript Access Notation).