XML Companion, The, Third Edition

Chapter 4. Physical structures (entities)

The markup described in previous chapters plays the important role of dividing a document into its logical components. It can also be useful to split documents into physical components. Entities allow components to be shared and more easily managed, for unusual characters to be easily represented, and for non-XML data to be included in the document.

It needs to be acknowledged that the least popular aspects of the XML standard are its entity-based features. Some of the adjunct standards described in later chapters attempt to replicate and improve on these features, using simpler techniques (such as XInclude (see Chapter 12) and XLink (see Chapter 27)). Applications of XML, including XML Schema and XSLT ...