FreeBSD -like operating system, a descendant of AT & T Unix under the BSD, the Berkeley. FreeBSD runs on PC-compatible systems, families of x86, including Microsoft Xbox, as well as the DEC Alpha, Sun UltraSPARC, IA-64, AMD64, PowerPC, NEC PC-98, ARM. Preparing to support architecture MIPS.
FreeBSD is developed as an integrated operating system. Kernel source code, device drivers and basic user programs (so called. Userland), such as shells, etc., contained in one tree, version control systems (up to May 31, 2008 - CVS, now - SVN). This differs from the FreeBSD Linux - another free UNIX-like operating system - in which the kernel is developed by one group of developers, and a set of custom programs - other (eg, the project GNU), and numerous groups gather it all together and released in the form of various distributions Linux.