As families go, the Linux operating system family has become the family among the Top500 supercomputers, running on 89.20% of all systems. Proprietary Unix, which used to the the preferred OS for these supercomputers in the 1990s is down to 5% share, and Windows is reported to be running on exactly 5 systems, for a 1% share.
With measured performance of nearly 2 petaflops and theoretical performance of more than 2 petaflops, these are some seriously high-performance machines! But more interesting is that Linux is the design center of a next-generation supercomputer aimed at cracking the exaflop barrier. Yet again we see validation that open source is a superior basis for innovation.