Public Domain Software, including: Djbdns, Icon (programming Language), Worldwideweb, Qmail, Sqlite, Otter (theorem Prover), Metapost, Mingw, Blast, ... Language), Cmu Common Lisp, Mpich, X-12-arima

Hephaestus Books represents a new publishing paradigm, allowing disparate content sources to be curated into cohesive, relevant, and informative books. To date, this content has been curated from Wikipedia articles and images under Creative Commons licensing, although as Hephaestus Books continues to increase in scope and dimension, more licensed and public domain content is being added. We believe books such as this represent a new and exciting lexicon in the sharing of human knowledge. This particular book is a collaboration focused on Public domain software.

More info: Public domain software is software that has been placed in the public domain, in other words there is absolutely no ownership (such as copyright) of the intellectual property that the software represents.