Polymorphism as a tool for updating and versioning of software
This document specifies a syntax created by subsetting an existing, widely used international text processing standard (Standard Generalized Markup Language, ISO 8886(E) as amended and corrected) for use on the World Wide Web.It is a product of the XML Core Working Group as part of the XML Activity. As a convenience to readers, it incorporates the changes dictated by the accumulated errata (available at to the Fourth Edition of XML 1.0, dated 16 August 2006.characters with both precomposed and base diacritic forms) match only if they have the same representation in both strings. (Of strings and rules in the grammar:) A string matches a grammatical production if it belongs to the language generated by that production.(Of content and content models:) An element matches its declaration when it conforms in the fashion described in the constraint [VC: Element Valid].] [Definition: Marks a sentence describing a non-binding recommendation included to increase the chances that XML documents can be processed by the existing installed base of SGML processors which predate the Web SGML Adaptations Annex to ISO 8879.] [Definition: A data object is an XML document if it is well-formed, as defined in this specification.
XML provides a mechanism to impose constraints on the storage layout and logical structure.This version of the XML specification may be distributed freely, as long as all text and legal notices remain intact.[Definition: A violation of the rules of this specification; results are undefined.[Definition: A software module called an XML processor is used to read XML documents and provide access to their content and structure.] [Definition: It is assumed that an XML processor is doing its work on behalf of another module, called the application.] This specification describes the required behavior of an XML processor in terms of how it must read XML data and the information it must provide to the application.XML was developed by an XML Working Group (originally known as the SGML Editorial Review Board) formed under the auspices of the World Wide Web Consortium (W3C) in 1996.
It was chaired by Jon Bosak of Sun Microsystems with the active participation of an XML Special Interest Group (previously known as the SGML Working Group) also organized by the W3C.