The Element element is used to define an element. (As mentioned previously, awkward sentences like this are hard to avoid with this standard). The Name attribute specifies the name of the element to be defined:
<element name="book" ... /> <!-- DTD EQUIVALENT: <!ELEMENT book ...> -->
This definition permits the 'book' element to occur within a conforming document instance:
Note that the Element element may be empty, as in the example above, but complex element definitions require this element to be a container for other instruction elements.
In the simplest possible form of declaration, the Element element is not only empty, but also has no attributes. This indicates that the element may contain ...