This single element can comprise any number of nested sub-elements. Elements consist of two tags, an opening and a closing tag. Text can be contained between the element tags and is considered part of the element. Empty elements are also supported. Elements can have attributes which further refine or modify element behaviour.
Most elements identify the nature of the contents they surround.
The logical structure of an XML document indicates how it is built, what elements can be included and in what order. The description element also has an attribute 'about', which tells us which web page this selection of XML is describing. The value of the attribute 'about' is the URL of the webpage. Brief descriptions and links to web pages and suppliers are given. The DOM defines interfaces, properties and methods to manipulate XML documents.