Python validating sax parser
There are many other text encodings that predate Unicode, such as ASCII and ISO/IEC 8859; their character repertoires in almost every case are subsets of the Unicode character set.
XML allows the use of any of the Unicode-defined encodings, and any other encodings whose characters also appear in Unicode.
IETF RFC:3023, now superseded by RFC:7303, gave rules for the construction of Internet Media Types for use when sending XML. Further guidelines for the use of XML in a networked context appear in RFC 3470, also known as IETF BCP 70, a document covering many aspects of designing and deploying an XML-based language.
The material in this section is based on the XML Specification.
Except for a small number of specifically excluded control characters, any character defined by Unicode may appear within the content of an XML document.
XML includes facilities for identifying the encoding of the Unicode characters that make up the document, and for expressing characters that, for one reason or another, cannot be used directly.
In computing, Extensible Markup Language (XML) is a markup language that defines a set of rules for encoding documents in a format that is both human-readable and machine-readable.
The W3C's XML 1.0 Specification It is a textual data format with strong support via Unicode for different human languages.
Several schema systems exist to aid in the definition of XML-based languages, while programmers have developed many application programming interfaces (APIs) to aid the processing of XML data.Disparate systems communicate with each other by exchanging XML messages.The message exchange format is standardised as an XML schema (XSD). XML has come into common use for the interchange of data over the Internet.The characters between the start-tag and end-tag, if any, are the element's content, and may contain markup, including other elements, which are called child elements.An example is , where the name of the attribute is "number" and its value is "3".
XML-based formats have become the default for many office-productivity tools, including Microsoft Office (Office Open XML), Open and Libre Office (Open Document), and Apple's i Work. Apple has an implementation of a registry based on XML. Many of these standards are quite complex and it is not uncommon for a specification to comprise several thousand pages.