1. What does DTD stand for? Document Type Definition or Document Type Declaration

2. What is the purpose of a DTD? It defines the document structure with a list of legal elements and attributes, the data that can be contained in an element or attribute, and the order of elements.

3. What is the meaning of this declaration in a DTD: <!ELEMENT to (#PCDATA)>? It means that the to element will contained parsed character data

4. What is the meaning of this declaration in a DTD: <!ELEMENT book (title, author, price, year)> It means that a book element will contain the subelements title, author, price, and year, in exactly that order.

5. What is the meaning of this declaration in a DTD: <!ELEMENT bookstore ((cd | book)+)> It means that a bookstore element can contain cd or book elements and that it must contain at least one or more of these elements.