OpenBSD is a multi-platform 4.4BSD-based operating system with a focus on security.

OpenBSD was forked from netbsd by project leader Theo de Raadt in late 1995. The motto of the OpenBSD project is "free, functional, secure".
Links
- Website: http://www.openbsd.org
- Distrowatch: http://distrowatch.com/table.php?distribution=openbsd
- WIkipedia: http://en.wikipedia.org/wiki/Openbsd