XML Schema is a full-featured language for describing the structure of XML documents. However, it cannot express everything there is to know about an instance or the data it contains. This chapter explains how you can extend XML Schema to include additional information for users and applications.
There are two places to include extensions in XSDL: annotations and non-native attributes. In this section, we will discuss the mechanics of defining each of these kinds of extensions. In later sections, we will explore how extensions might best be used.
In XSDL, annotations are represented by an
annotation element, whose syntax is ...