OpenBSD项目提供了一份免费、多平台的、基于4.4 BSD的UNIX操作系统。我们的成就在于强调其可移植性、标准化、正确性、安全性以及集成的密码应用技术。OpenBSD支持大多数SVR4（如 Solaris）程序的二进制仿真，也支持FreeBSD、Linux、BSD/OS、SunOS和HP-UX程序。OpenBSD可从我们的FTP站点免费获得，也可以通过并不昂贵的三CD套装获得。
Theo de Raadt has announced the release of OpenBSD 4.3: "We are pleased to announce the official release of OpenBSD 4.3. This is our 23rd release on CD-ROM (and 24th via FTP). We remain proud of OpenBSD's record of more than ten years with only two remote holes in the default install. As in our previous releases, 4.3 provides significant improvements, including new features, in nearly all areas of the system. Highlights include: GNOME 2.20.3, GNUstep 1.14.2, KDE 3.5.8, Mozilla Firefox 2.0.0.12, Mozilla Thunderbird 2.0.0.12, MySQL 5.0.51a, OpenMotif 2.3.0, OpenOffice.org 2.3.1, PostgreSQL 8.2.6, Xfce 4.4.2." Read the release announcement and
release notes for a detailed list of changes and new features. Installation ISO images for a variety of architectures are available for download from these OpenBSD mirrors and also via BitTorrent; quick links to the i386 and amd64 installation images:
i386/install43.iso (203MB, MD5),
amd64/install43.iso (222MB, MD5).
