[Introduction][Goals of XML][XML vs HTML][How to write XML]

The Official Goals of XML

XML shall be straightforwardly usable over the internet

XML shall support a wide variety of applications

XML is already being used for exchanging information among financial programs, for distributing and updating programs, for writing invoices for delivery over the phones

XML shall be compatible with SGML

It shall be easy to write programs which process XML documents

XML documents should be human readable and reasonably clear

The XML should be prepared quicly

XML should be easy to create

How can XML be Used?
It is important to know that XML was designed to store, carry and exchange data. It was not designed to display data
An XML application is normally defined by creating a document type definition –DTD which is an optional component of an XML document. A DTD is like a database schema. It defines and names the elements that can be used in the document, the order in which the elements will appear, the element attributes that can be used etc. To use an XML application you usually include its DTD in your XML document. Having the DTD in the document restricts the elements and structure that you can use so that your document is forced to conform to the application standard.

Real Word Uses of XML

Storing Databases

Structuring documents

Storing Vector Graphics (VML)

Describing Multimedia Applications

Definning channels

Describing software packages and the indeterdependencies

Communicating among applications

Sending electronicn bbusiness cards vie e-mai

XML can Separate Data from HTML

With XML, your data is stored outside your HTML.

When HTML is used to display data, the data is stored inside your HTML. With XML, data can be stored in separate XML files. This way you can concentrate on using HTML for data layout and display, and be sure that changes in the underlying data will not require any changes to your HTML.

XML data can also be stored inside HTML pages as "Data Islands". You can still concentrate on using HTML only for formatting and displaying the data.

XML is used to Exchange Data

XML, data can be exchanged between incompatible systems.

In the real world, computer systems and databases contain data in incompatible formats. One of the most time consuming challenges for developers has been to exchange data between such systems over the Internet.

Converting the data to XML can greatly reduce this complexity and create data that can be read by many different types of applications.

XML and B2B

With XML, financial information can be exchanged over the Internet.
Expect to see a lot about XML and B2B (Business To Business) in the near future
XML is going to be the main language for exchanging financial information between businesses over the Internet. A lot of interesting B2B applications are under development.XML can be used to Share Data

With XML, plain text files can be used to share data.

Since XML data is stored in plain text format, XML provides a software- and hardware-independent way of sharing data.
This makes it much easier to create data that different applications can work with. It also makes it easier to expand or upgrade a system to new operating systems, servers, applications, and new browsers.
XML can be used to Store Data

With XML, plain text files can be used to store data.
XML can also be used to store data in files or in databases. Applications can be written to store and retrieve information from the store, and generic applications can be used to display the data.

XML can make your Data more Useful

With XML, your data is available to more users.

Since XML is independent of hardware, software and application, you can make your data available to more than only standard HTML browsers.
Other clients and applications can access your XML files as data sources, like they are accessing databases. Your data can be made available to all kinds of "reading machines" (agents), and it is easier to make your data available for blind people, or people with other disabilities.

XML can be used to Create new Languages
XML is the mother of WAP and WML.
The Wireless Markup Language (WML), used to markup Internet application for handheld devices like mobile phones, is written in XML.

If Developers have Sense

If they do have sense, all future applications will store its data in XML.

The future might give us word processors, spreadsheet applications and databases that can read each others data in a pure text format, without any conversion utilities in between.

We can only pray that Microsoft and all the other software vendors will agree.

Displaying XML Documents

Style Sheet Linking

You can you a Cascading Style Sheet wich is used for HTML or an XSL-eXtensible Style Language which is specifically used for the XML. XSL is more powerfull than CSS.

Data binding

This requires you to create an HTML page and link the XML document to it and bind standard HTML elemtns such as table to the XML elements.

Scripting

You create an HTML page, link the XML document to it and access and display individual XML by writing script code (Javascript or Vbscript. The browser then exposes the XML document as a Document Object Module- DOM.