Scientific Linux (SL) is a discontinued Linux distribution produced by Fermilab, CERN, DESY and by ETH Zurich. It is a free and open-source operating system based on Red Hat Enterprise Linux. This product is derived from the free and open-source software made available by Red Hat, but is not produced, maintained or supported by them. In April 2019, it was announced that feature development for Scientific Linux would be discontinued, but that maintenance will continue to be provided for the 6.x and 7.x releases through the end of their life cycles. Fermilab and CERN will utilize CentOS Stream and AlmaLinux for their deployment of 8.x release instead. Fermilab already had a Linux distribution known as Fermi Linux, a long-term support release based on Red Hat Enterprise Linux. CERN was creating their next version of CERN Linux, also based on RHEL. CERN contacted Fermilab about doing a collaborative release. Connie Sieh was the main developer and driver behind the first prototypes and initial release. The first official release of Scientific Linux was version 3.0.1, released on May 10, 2004. In 2015, CERN began migrating away from Scientific Linux to CentOS. Scientific Linux is now maintained by a cooperative of science labs and universities. Fermilab is its primary sponsor. The primary purpose of Scientific Linux is to produce a common Linux distribution for various labs and universities around the world, thus reducing duplicated effort. The main goals are to have everything compatible with Red Hat Enterprise Linux with only minor additions and changes, and to allow easy customization for a site, without disturbing the Linux base. Unlike other distributions such as Poseidon Linux, it does not contain a large collection of scientific software as its name may suggest. However, it provides good compatibility to install such software. Scientific Linux is derived from Red Hat Enterprise Linux without protected components such as Red Hat trademarks, thus making it freely available. New releases are typically produced about two months after each Red Hat release.