This short description is about the work of XForms. Before talking about XForms it's important to understand the concept of forms. Forms are to collect the data so we should not get surprised if we say XForms is basically depending on instance data. Instance data are these data which are based on XML. The data are defined in the terms of XPath's internal tree illustration and dispensation of XML.
It may look odd at first to relate XPath with XForms. However, XPath is the well-known as the ordinary layer between XSLT and XPointer. Since XForms
There was a question on Mark Birbeck's mind. Should Xpath feature CSS? "But while some sort of convergence of XPath and CSS selectors may seem an obvious thought to many, the CSS 'language' continues to resist being brought up to date, and instead exists in a strange, murky world, of 'quirkarounds' and 'standards-proprietary' syntax. (As people require the ability to address other parts of the source tree, new selection mechanisms have to be added, but in a way that doesn't affect existing rules -- resulting in 'quirky workarounds', and syntax that is
Forms are for collecting data, so it's not surprising that the most important concept in XForms is "instance data", an internal representation of the data mapped to the familiar "form controls". Instance data is based on XML and defined in terms of XPath's internal tree representation and processing of XML.
It might seem strange at first to associate XPath and XForms. XPath is best known as the common layer between XSLT and XPointer, not as a foundation for web forms. As XForms evolved, however, it became apparent that forms needed greater structure
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