This directory contains the http://www.htmlpp.org/ website from 2000.
htmlpp is a HTML preprocessing tool from iMatix Corporation sprl. Contemporaneous source code is available on GitHub. Later versions became part of the iMatix Base package, and were included in OpenAMQ.
You can view this website at:
https://imatix-legacy.github.io/htmlpp.org/
(which has been fixed up to use relative links where necessary).