Red Hat Enterprise Linux
Red Hat Enterprise Linux (RHEL) is a Linux distribution developed by Red Hat and targeted toward the commercial market. Red Hat Enterprise Linux is released in server editions for x86, x86_64, Itanium, PowerPC and IBM System z architectures, and desktop editions for x86 and x86_64 processors.
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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.