3.4. XML Document Logical Structure

The logical structure of an XML document consists of declarations, elements, character references, comments, and processing instructions.

Table 3-4. Structure of an XML Document
Structure Consists of… Part Referred to as… Notes
Logical Markup Declarations



Character references

CDATA sections



Processing instructions
  • Explicit markup indicates each type of markup.

  • The logical and physical structures must nest properly.

Physical One or more storage units Entities
  • Entities have content and a name.

  • They can be parsed or unparsed.

  • They can refer to other entities.

  • Each document has a document entity.

  • All have content.

  • All are identified by name, except the document entity and an external ...

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