XML is rapidly being integrated into all kinds of computer systems, including financial systems used by banks. The rigidity of XML as a markup language will no doubt make these systems more robust. The facet of XML that allows errors to be detected is the schema, which is a construct that allows XML developers to define the format and structure of XML data.
This tutorial introduces you to schemas, including the two major types that are used to define data for XML documents. The first of these schema types, DTDs, is examined in detail in this tutorial, while the latter is saved for a later lesson. This tutorial explores the inner workings of DTDs and shows you how to create DTDs from scratch.
In this tutorial, you'll learn
- How XML allows you to create custom markup languages
- The role of schemas in XML data modeling
- The difference between the types of XML schemas
- What constitutes valid and well-formed documents
- How to declare elements and attributes in a DTD
- How to create and use a DTD for a custom markup language