El CERN (European Organization for Nuclear Research) European, or the cathedral of science as many call it, he was already known for using a GNU / Linux distribution for his computers and supercomputer. Specifically, it was Scientific Linux, based on RHEL, but then they created the most modern CCentSO (CERN CentOS), a version of CentOS special for CERN applications and that you can find and download for free on their website, as was the case with Scientific Linux.
CERN is one of the largest and most important underground laboratories in the world. Many of the best scientists from various countries work there and analyze the origins of the universe, matter, and many things important for the future of humanity. And all thanks to the particle accelerator, the Large Hadron Collider (LHC). During the experiments thousands of gigabytes of information are generated that must be processed and stored quickly.
That is what the supercomputer in the data center they have there is in charge of, with GNU / Linux, by the way ... But regardless of all the praise that I can give to this great laboratory, the news now is that are stopping using Microsoft software and starting to use open source software. This allows them to save large amounts of money on licenses to be able to invest in other more productive purposes.
Una price increase in licenses they have made this possible. CERN cannot afford to waste so much money on licenses and they are betting on free software. For example, a year ago they launched MAlt (Microsoft Alternatives Project), whose name says it all. They are looking for alternatives, they are migrating systems and making use of free and open source software for the work that their workers do there. Without a doubt very good news. I hope that more and more large organizations and companies will follow this same path.
First a small correction: Scientific Linux is a spin of Fedora (of course it is based on RHEL as such).
What surprises me is that CERN hasn't done it before, for example when they went from Fedora to CentOS (notabene also dropped from Fedora and RHEL). This has already been almost a revolution, because once they have put it, why have they not made a thorough change?
A gossip: Tim Berners-Lee worked at CERN (I don't know if he still does) when he created HTML and the World Wide Web. In fact, the proposal arose from CERN's own needs.