cxml and SAX
This document describes the SAX package, a part of Closure XML (or cxml for short, an XML parser written Common Lisp).
It also covers its cousin, the HAX package, which involves integration between cxml's libraries and the Closure HTML parser.
SAX is well-known to anyone who has used XML from Java; indeed it is originally a Java API.
In cxml, however, the package called SAX is a Lisp package. (It's called SAX because it follows the same concept as the well-known Java API of the same name.)