Special Edition Using XML, Second Edition

XML Document Structure

XML documents are text documents, which are commonly denoted as XML documents by use of the .xml extension. There are no restrictions on the length of the XML document; however, at a certain point, a document that is too long may become difficult to navigate or use in conjunction with XML software.

Now let's take a look at some of the physical constructs of XML documents.

The XML Declaration

Every XML document should begin with the XML Declaration, which takes the following form:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?> 

The XML declaration always starts with the “<?xml” and always ends with “?>”. Additionally, there are three attributes that are also used in the XML Declaration:

• version— The version attribute ...