Can a root element type be explicitly declared in the DTD?
No. This is done in the document’s Document Type Declaration, not in the DTD. 36. I keep hearing about alternatives to DTDs. What’s a Schema? The W3C XML Schema recommendation provides a means of specifying formal data typing and validation of element content in terms of data types, so that document type designers can provide criteria for checking the data content of elements as well as the markup itself. Schemas are written in XML Document Syntax, like XML documents are, avoiding the need for processing software to be able to read XML Declaration Syntax (used for DTDs). There is a separate Schema FAQ at http://www.schemavalid.com. The term ‘vocabulary’ is sometimes used to refer to DTDs and Schemas together. Schemas are aimed at e-commerce, data control, and database-style applications where character data content requires validation and where stricter data control is needed than is possible with DTDs; or where strong data typing is required. They are usually unnecessary for tradition
