In the context of web documents, the term HTML validator technically refers
to validation using DTDs by SGML tools. However, the common (non technical)
use of the term refers to checking an HTML document for various problems
using some type of computerized checker, and not necessarily by using a DTD
with SGML tools. Furthermore, the term HTML validation for HTML 5 cannot
mean validation using a DTD because HTML 5 does not use a DTD.
