This enhances the functionality and interoperability of the Web.W3C maintains a public list of any patent disclosures made in connection with the deliverables of the group; that page also includes instructions for disclosing a patent.Markup encodes a description of the document's storage layout and logical structure.XML provides a mechanism to impose constraints on the storage layout and logical structure.It is a stable document and may be used as reference material or cited from another document.
1 Introduction 1.1 Origin and Goals 1.2 Terminology 2 Documents 2.1 Well-Formed XML Documents 2.2 Characters 2.3 Common Syntactic Constructs 2.4 Character Data and Markup 2.5 Comments 2.6 Processing Instructions 2.7 CDATA Sections 2.8 Prolog and Document Type Declaration 2.9 Standalone Document Declaration 2.10 White Space Handling 2.11 End-of-Line Handling 2.12 Language Identification 3 Logical Structures 3.1 Start-Tags, End-Tags, and Empty-Element Tags 3.2 Element Type Declarations 3.2.1 Element Content 3.2.2 Mixed Content 3.3 Attribute-List Declarations 3.3.1 Attribute Types 3.3.2 Attribute Defaults 3.3.3 Attribute-Value Normalization 3.4 Conditional Sections 4 Physical Structures 4.1 Character and Entity References 4.2 Entity Declarations 4.2.1 Internal Entities 4.2.2 External Entities 4.3 Parsed Entities 4.3.1 The Text Declaration 4.3.2 Well-Formed Parsed Entities 4.3.3 Character Encoding in Entities 4.4 XML Processor Treatment of Entities and References 4.4.1 Not Recognized 4.4.2 Included 4.4.3 Included If Validating 4.4.4 Forbidden 4.4.5 Included in Literal 4.4.6 Notify 4.4.7 Bypassed 4.4.8 Included as PE 4.4.9 Error 4.5 Construction of Entity Replacement Text 4.6 Predefined Entities 4.7 Notation Declarations 4.8 Document Entity 5 Conformance 5.1 Validating and Non-Validating Processors 5.2 Using XML Processors 6 Notation A References A.1 Normative References A.2 Other References B Character Classes C XML and SGML (Non-Normative) D Expansion of Entity and Character References (Non-Normative) E Deterministic Content Models (Non-Normative) F Autodetection of Character Encodings (Non-Normative) F.1 Detection Without External Encoding Information F.2 Priorities in the Presence of External Encoding Information G W3C XML Working Group (Non-Normative) H W3C XML Core Working Group (Non-Normative) I Production Notes (Non-Normative) J Suggestions for XML Names (Non-Normative) Extensible Markup Language, abbreviated XML, describes a class of data objects called XML documents and partially describes the behavior of computer programs which process them.
This edition supersedes the previous W3C Recommendation of 16 August 2006.
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XML has been designed for ease of implementation and for interoperability with both SGML and HTML.
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