OpenBSD

OpenBSD is an open source Unix-like Operating System. It is free to download, copy and modify. It is not similar to Linux in a sense because it was based on the 4.4BSD Operating System developed at the University of California at Berkeley (UCB). OpenBSD's mascot is puffy the Blowfish. OpenBSD Project Home Page OpenBSD is written with C programming language.

OpenBSD 6.2
The current OpenBSD version is 6.2:

Since version 6.0 OpenBSD does not sell any more CD's. OpenBSD operates on donations only, please consider a donation. Donations can be made directly to Theo de Raadt or the OpenBSD Foundation.

Ported programs that orginated at OpenBSD

 * OpenSSH is a side-project of OpenBSD. It was forked from ssh with an old version that had little license restrictions and is compatible now with ssh 2.0.
 * pf was created at OpenBSD first (before being ported to other BSD's). Pf stands for Packet Filter and is a layer 3+ firewall.  It was created to replace ipf.
 * LibreSSL, because noone before looked at OpenSSL (different affiliation)

Release Song
Since release 3.0 OpenBSD has released a promotional song with its CD, it makes the project more hip this way. The songs and their lyrics can be found here

Hackathons
Hackathons are get-togethers of the programmers of OpenBSD. Since OpenBSD makes money by selling CD's and other merchandise, there is enough money to pay some developers travel, room and board. At a hackathon which spans usually over a week or so the programmers do a lot of code and can help others that need some information at hand. Marc.info can be used to track changes to the openbsd source tree which gets updated very often during a hackathon (otherwise one can subscribe to the list through majordomo).

Export Restrictions
FreeBSD recently implemented ACPI code in its implemenatation that has export restrictions. OpenBSD has no such export restrictions since the project is based in Canada which is known for its liberal export rules.