Since the debut of Oracle Linux release 4, in 2006, it has been completely free to use and easy to download. Major and update release have been free for more than 14 years. Errata releases have been freely available since 2012. Free source code, free binaries, free updates, free errata, freely redistributable – without having to sign any documents with Oracle and no need to remove trademarks and copyrights – and free for production use. Oracle Linux has had a release for every equivalent Red Hat Enterprise Linux (RHEL) release, 4, 5, 6, 7, and most recently 8. Oracle Linux releases consistently track RHEL’s – minor releases are usually available within five business days; errata typically within 24 hours; and major releases within three months. The identical version of Linux is available for both free and supported systems. This makes Oracle Linux an ideal choice for development, testing, and production use. You decide which support coverage is best for each individual system while keeping all systems up-to-date and secure. Compatible and enhanced Oracle Linux is 100% application binary compatible with Red Hat Enterprise Linux (RHEL). Since the 2006 launch, enterprises have been running Oracle Linux with no compatibility bugs logged. Oracle offers a choice of two kernels: the Unbreakable Enterprise Kernel (UEK) for Oracle Linux or the Red Hat Compatible Kernel (RHCK). Both are supported by Oracle. UEK offers extensive performance and scalability improvements to the process scheduler, memory management, file systems, and the networking stack. We believe the source for the kernel you run should be easy to pick apart. That’s why we publish the UEK source code, complete with the original mainline changelog and our changelog on GitHub. Whether running on UEK or RHCK, Oracle Linux is fully compatible with (RHEL).