FreeBSD

From IeXwiki

FreeBSD is a free, open source, Unix-like operating system descended from AT&T Unix via the Berkeley Software Distribution (BSD) branch through 386BSD and 4.4BSD. It runs on processors compatible with the Intel x86 family, as well as on the DEC Alpha, the UltraSPARC processors by Sun Microsystems, the Itanium (IA-64) and AMD64 processors. Support for the PowerPC and ARM architectures is in development.

FreeBSD is developed together as an entire operating system. The kernel, all of the expected userland utilities such as the shell and the device drivers are held in the same source code revision tracking tree (CVS). This is in contrast to Linux, a similar and more well known free Unix-clone, which is developed as a kernel by one group, userland utilities by others such as the GNU project, and put together with applications into distributions that package all the parts together by others. As an operating system, FreeBSD is generally regarded as being quite reliable and robust, and of the operating systems that accurately report uptime remotely, FreeBSD is the only free operating system listed in Netcraft's longest uptime list for web servers.