OpenBSD's founder, Theo de Raadt, started as a NetBSD developer several years ago. He had several strong disagreements, on many fronts, with the NetBSD developers about how the operating system should be developed. Eventually, he went out on his own and founded the OpenBSD Project, attracting quite a few like-minded developers to work with him. The OpenBSD team introduced several ideas into the open-source OS world that are now taken for granted, such as public access to the CVS repository and commit logs.
The OpenBSD team quickly established an identity of its own as a security-focused group and is now one of the best-known types of open-source BSD. Today, major companies such as Adobe Systems rely on OpenBSD to provide a reliable, secure operating system.
Today, OpenBSD is a BSD-based UNIX-like operating system with a fanatical attention to security, correctness, usability, and freedom. It runs on many different sorts of hardware including the standard "Intel PC" (i386), the Macintosh (mac68k and macppc), Sun's Sparc (sparc and sparc64), Compaq's Alpha (alpha), and more. OpenBSD puts almost all its efforts into security features, security debugging, and code correctness. The OpenBSD folks have demonstrated that correct code has a much lower chance of failing, and hence greater security. While some other BSDs focus on different goals, OpenBSD strives to be the ultimate secure operating system.
The OpenBSD team continually improves the operating system to enhance its security, stability, and freedom. This includes everything from the actual code in the operating system, to the online manual (which has a nearly legendary quality in the free software community), to the debugging and development environment, to the continuous software license auditing.