Core data error validating url store
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 XML has come into common use for the interchange of data over the Internet.IETF RFC:3023, now superseded by RFC:7303, gave rules for the construction of Internet Media Types for use when sending XML.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.The Unicode character set can be encoded into bytes for storage or transmission in a variety of different ways, called "encodings".Unicode itself defines encodings that cover the entire repertoire; well-known ones include UTF-8 and UTF-16.Except for a small number of specifically excluded control characters, any character defined by Unicode may appear within the content of an XML document.
Encodings other than UTF-8 and UTF-16 are not necessarily recognized by every XML parser.extends the set of allowed characters to include all the above, plus the remaining characters in the range U 0001–U 001F.At the same time, however, it restricts the use of C0 and C1 control characters other than U 0009 (Horizontal Tab), U 000A (Line Feed), U 000D (Carriage Return), and U 0085 (Next Line) by requiring them to be written in escaped form (for example U 0001 must be written as or its equivalent).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.
XML is used extensively to underpin various publishing formats.