FreeBSD 9.1 is the second release from the stable/9 branch, which improves on the stability of FreeBSD 9.0 and introduces some new features. Some of the highlights: new Intel GPU driver with GEM/KMS support; netmap(4) fast userspace packet I/O framework; ZFS improvements from Illumos project; CAM Target Layer, a disk and processor device emulation subsystem; optional new C++11 stack including LLVM libc++ and libcxxrt; jail devfs, nullfs, zfs mounting and configuration file support; POSIX2008 extended locale support, including compatibility with Darwin extensions; oce(4) driver for Emulex OneConnect 10Gbit Ethernet card.
 
About FreeBSD
FreeBSD is a UNIX-like operating system for the i386, amd64, IA-64, arm, MIPS, powerpc, ppc64, PC-98 and UltraSPARC platforms based on U.C. Berkeley's "4.4BSD-Lite" release, with some "4.4BSD-Lite2" enhancements. It is also based indirectly on William Jolitz's port of U.C. Berkeley's "Net/2" to the i386, known as "386BSD", though very little of the 386BSD code remains. FreeBSD is used by companies, Internet Service Providers, researchers, computer professionals, students and home users all over the world in their work, education and recreation. FreeBSD comes with over 20,000 packages (pre-compiled software that is bundled for easy installation), covering a wide range of areas: from server software, databases and web servers, to desktop software, games, web browsers and business software - all free and easy to install.