Distros

ReactOS is a free and open-source operating system based on the best design principles found in the Windows NT architecture. Written completely from scratch, ReactOS is not a Linux-based system and it shares none of the UNIX architecture. The main goal of the ReactOS project is to provide an operating system which is binary compatible with Windows. This will allow Windows applications and drivers to run as they would on a Windows system. Additionally, the look and feel of the Windows operating system is used, such that people accustomed to the familiar user interface of Windows would find using ReactOS straightforward. The ultimate goal of ReactOS is to allow people to use it as an alternative to Windows without the need to change software they are used to.

RebeccaBlackOS is a Debian-based live distribution which can be used to run Wayland desktop sessions. RebeccaBlackOS can run a number of popular open source desktop environments on top of a Wayland graphical session. The distribution was (and remains) one of the only Linux distributions to run a Wayland session from live media. The distribution is available in 32-bit and 64-bit builds for the x86 architecture.

Recalbox is a dedicated operating system for running video games on emulated retro and console platforms. Recalbox can also be used to run the Kodi media centre. The distribution's interface is primarily navigated with a console game controller, though keyboard support is available for many functions.

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. All of Red Hat's official support and training and the Red Hat Certification Program centres around the Red Hat Enterprise Linux platform. Red Hat uses strict trademark rules to restrict free re-distribution of its officially supported versions of Red Hat Enterprise Linux, but still freely provides its source code. Third-party derivatives can be built and redistributed by stripping away non-free components.

RED OS is an independently-developed Russian Linux distribution for workstations and servers. It uses the RPM and DNG tools for package management. The workstation edition provides a choice of three desktops, KDE Plasma, GNOME and MATE, while the server variant includes a custom server administration utility called RED ADM. The distribution is developed by Russia's RED SOFT, a company that also provides technical support and Linux training, as well as various administration, virtualisation and database software products.

Redcore Linux explores the idea of bringing the power of Gentoo Linux to the masses. It aims to be a very quick way to install a pure Gentoo Linux system without spending hours or days compiling from source code, and reading documentation. To achieve this goal, Redcore provides a repository with pre-built binary packages which receives continuous updates, following a rolling release model.

Redox is a Unix-like, general-purpose, microkernel-based operating system written in Rust. Redox aims to bring the innovations of Rust to a modern microkernel. The project also provides a full set of custom programs and tries to be a complete alternative to Linux and BSD. Redox OS attempts to be source-compatible with Linux and the BSD family, making porting between operating systems easier. Redox is available in Server and Desktop editions, featuring components of the COSMIC desktop in the latter edition.

Refracta is a Linux distribution based on Devuan GNU+Linux (a systemd-free fork of Debian), designed primarily for home computer users and also for use as a system rescue and recovery disk. It provides a simple and familiar layout using the Xfce desktop. Other desktop environments and additional software packages are available from the Devuan package repository. Besides providing a Linux distribution on a live CD, the project also develops useful tools, such as refractainstaller, refractasnapshot and refracta2usb which allow users to customize the installation and create custom live CD or live USB images.