Chapter 1. Writing XML
The XML specification defines how to write a document in XML format. XML is not a language itself. Rather, an XML document is written in a custom markup language, according to the XML specification. For example, there could be custom markup languages describing genealogical, chemical, or business data, and you could write XML documents in each one.
Every custom markup language created using the XML specification must adhere to XML’s underlying grammar. Therefore, that is where I will start this book. In this chapter, you will learn the rules for writing XML documents, regardless of the specific custom markup language in which you are writing.
Officially, custom markup languages created with XML are called XML applications ...