Parameter entities may be used to link the content of additional DTD files to a DTD, or as an abbreviation for frequently repeated declarations. Parsed character data is text that will be examined by the parser for entities and markup. A system that detects a pause in the speaker's voice and somehow marks that time for later use. That something may include presentation, calculation, or anything else that seems appropriate. The XML declaration is itself a processing instruction.
Recursive programming is especially well-suited to parsing nested markup structures.
The first element in a document. The root element is not contained by any other elements and forms the base of the tree structure created by parsing the nested elements. The relationship between a document's content and its structure. The elements within a document which are not part of the main body text. Often called side bars, notes, marginalia, margin notes.