Family of second-generation microkernels, generally used to implement Unix-like operating systems, but also used in a variety of other systems.

Jochen Liedtke, Germany

Family of second-generation microkernels, generally used to implement Unix-like operating systems, but also used in a variety of other systems.

Jochen Liedtke, Germany

Operating system for the HITAC L-320, a general-purpose intelligent system with such functions as data entry, billing, and remote job entry.

Hitachi, Japan

Extremely fast microkernel available for x86, ARM, MIPS and other architectures.

University of Karlsruhe, Germany, Germany

Distributed real-time OS for laboratory control.

USA

Local area heterogeneous network operating system.

Universidad Nacional de San Luis, Spain

Network operating system available from multiple vendors and developed by Microsoft in cooperation with 3Com Corporation. It was designed to succeed 3Com's 3+Share network server.

Microsoft, USA

Peer-to-peer local area network (LAN) operating system for DOS, Microsoft Windows and OS/2. LANtastic supports Ethernet, ARCNET and Token Ring adapters.

Artisoft, USA

Last version.

Operating system for TRS-80. Originally stood for "Lobo Drives Operating System.

Logical Systems, USA

Linux Embedded Development Environment. Fork of the OpenWrt project and shared many of the same goals.

Firmware replacement for Lego Mindstorms programmable bricks.

Open source POSIX "compliant" Operating System for deeply embedded devices. Based on embOS. See Tauon.

Philippe Le Boulanger, France

Previously known as Open webOS, HP webOS and Palm webOS.

LG Electronics, Korea

Yggdrasil Linux/GNU/X. Early Linux distribution.

Yggdrasil Computing, USA

GNU/Linux-libre distribution for computers with minimal resources, such as the Ben Nanonote, ath9k-based Wi-Fi routers, and other hardware with emphasis on free software.

USA

LibreRTOS is a portable single-stack Real Time Operating System.

GNU/Linux-libre operating system for computers with minimal resources, such as the Ben Nanonote, ath9k based Wi-Fi routers. LibreWRT was merged to the libreCMC project in 2015.

Jason Self, Denver Gingerich, USA

Free operating system based on the FreeDOS kernel.

Corbin Davenport, USA

Open-source operating system for x86 computers, based on DR-DOS/OpenDOS 7.01.

Corbin Davenport, USA

Free and open-source operating system for set-top boxes, smartphones and tablet computers, based on the Android mobile platform.

See also List of Linux distributions. Alleged to be GNU/Linux see GNU/Linux naming controversy.

Linus Torvalds, Finland

Community-driven Linux distribution based on Debian and Ubuntu that strives to be a "modern, elegant and comfortable operating system which is both powerful and easy to use.

Clément Lefèbvre, Jamie Boo Birse, Kendall Weaver,, International

GUI environment for end users.

Apple, USA

Lisa Operating System.

Apple, USA

The Workshop is a program development environment and is almost entirely text-based, though it uses a GUI text editor.

Apple, USA

Also known as LMI. Used an operating system written in MIT's Lisp Machine Lisp.

USA

Project to revive the still unequalled systems that ran on Lisp Machines of the past (such as the still surviving Genera) this time making it free and running on standard/cheap hardware, instead of proprietary and requiring non-standard/expensive hardware.

Unix-like OS of the BSD family as a "singleserver" over the Mach microkernel.

Johannes Helander, Finland

Para-virtualised guest operating system which provides the primitives to create the system resources (blackboards, buffers, events, semaphores...) and the mechanisms to create threads, timers and the process scheduler.

FentISS, Spain

Small OS experiment being developed by a group of individuals.

Pascal Lacroix, Nicolas Regis-Constant, France

TCSEC A1-class secure system with kernel & hardware support for Type enforcement.

Distributed OS based on UNIX.

UCLA, USA

MIA LOS was meant to be another OS for gamers, like EOS.

Jonas Berlin, Finland

Research kernel.

Epita System Laboratory, France

Lawrence Timesharing System. Early Timesharing OS.

Lawrence Livermore Labs, USA

Aka LNG. Operating system primarly for the good old Commodore64 home-computer. There also is a native version for the successor Commodore 128.

Daniel Dallman, Germany

Unix-like real-time operating system from Lynx Software Technologies (formerly "LynuxWorks"). Sometimes known as the Lynx Operating System, LynxOS features full POSIX conformance and, more recently, Linux compatibility.

Was the commercial development of EDSAC computing platform, supported by British firm J. Lyons and Co.

J. Lyons and Co., UK