Classic Mac OS, Palm OS, System 7, OS/360 and successors, OS/2, Mac operating systems, Mac OS 8, Mac OS 9, FlexOS, System Settings, Fire OS, ZFS (z/OS file system), OS X Mavericks, Pop! OS, OS 2200, 4690 Operating System, BlackBerry OS, MacOS, HarmonyOS, Wear OS, AmigaOS, Glass OS, Red Star OS, OS/VS1, ChromeOS, Copland (operating system), High Performance File System, History of RISC OS, Darwin (operating system), System folder, Operating system, Internet OS, Haiku (operating system), OS X El Capitan, Usage share of operating systems, System 1, Rhapsody (operating system), Cherry OS (operating system), Domain/OS, Mobile operating system, MacOS Mojave

ReactOS, Mac OS X Leopard, Real-time operating system, Micro-Controller Operating Systems, TempleOS, Comparison of operating systems, List of operating systems, List of built-in macOS apps, Singularity (operating system), Hierarchical File System (IBM MVS), IBM OS/6, /e/ (operating system), Elementary OS, Mac OS X Snow Leopard, Disk operating system, Hobbyist operating system, List of Apple operating systems, OS-level virtualization, Maya (operating system), SharpOS, Inferno (operating system), Just enough operating system, COS (operating system), KaiOS, System suitcase, System 6, HiOS, Syllable Desktop, LynxOS, System Generation (OS), SystemStarter, Fuchsia (operating system), NixOS, AROS Research Operating System, THE multiprogramming system, Solus (operating system), Hierarchical File System (Apple), IBM System/360 Model 50, ZETA (operating system), Network operating system, Be File System, Kylin (operating system), List of Microsoft operating systems, Embedded operating system, Distributed operating system, IOS, Unity Operating System, BrickOS, MVS, Illumos

Classic Mac OS, Palm OS, System 7, OS/360 and successors, OS/2, Mac operating systems, Mac OS 8, Mac OS 9, FlexOS, System Settings, Fire OS, ZFS (z/OS file system), OS X Mavericks, Pop! OS, OS 2200, 4690 Operating System, BlackBerry OS, MacOS, HarmonyOS, Wear OS, AmigaOS, Glass OS, Red Star OS, OS/VS1, ChromeOS, Copland (operating system), High Performance File System, History of RISC OS, Darwin (operating system), System folder, Operating system, Internet OS, Haiku (operating system), OS X El Capitan, Usage share of operating systems, System 1, Rhapsody (operating system), Cherry OS (operating system), Domain/OS, Mobile operating system, MacOS Mojave, ReactOS, Mac OS X Leopard, Real-time operating system, Micro-Controller Operating Systems, TempleOS, Comparison of operating systems, List of operating systems, List of built-in macOS apps, Singularity (operating system), Hierarchical File System (IBM MVS), IBM OS/6, /e/ (operating system), Elementary OS, Mac OS X Snow Leopard, Disk operating system, Hobbyist operating system, List of Apple operating systems, OS-level virtualization, Maya (operating system), SharpOS, Inferno (operating system), Just enough operating system, COS (operating system), KaiOS, System suitcase, System 6, HiOS, Syllable Desktop, LynxOS, System Generation (OS), SystemStarter, Fuchsia (operating system), NixOS, AROS Research Operating System, THE multiprogramming system, Solus (operating system), Hierarchical File System (Apple), IBM System/360 Model 50, ZETA (operating system), Network operating system, Be File System, Kylin (operating system), List of Microsoft operating systems, Embedded operating system, Distributed operating system, IOS, Unity Operating System, BrickOS, MVS, Illumos, NCOS, HFS Plus, IBM System/370, IOS version history, Oberon (operating system), PlayStation 4 system software, TCP/IP stack fingerprinting, Tails (operating system), Android (operating system), Kernel (operating system), A2 (operating system), Bada (operating system), CentOS, PlayStation 3 system software, Mer (software distribution), Symbian, Robot Operating System, BlackBerry 10, DOS, Microsoft Windows, Xbox system software, Amoeba (operating system), Cmd.exe, Issues relating to iOS, Helios (operating system), Oracle Solaris, Unix-like, Ordnance Survey National Grid, SUPER-UX, FTOS, Kiosk software, Maemo, Stratis (configuration daemon), Plan 9 from Bell Labs, Architecture of Windows NT, Xenix, GNU, GEOS (16-bit operating system), Wii U system software, Pick operating system, Green Hills Software, Nintendo 3DS system software, Sprite (operating system), HyperOs HyperDrive, TRON project, IBM AIX, Fedora Linux, Design of the FAT file system, 64-bit computing, Linux, Novell Embedded Systems Technology, Hibernation (computing), Environment variable, System 7 (disambiguation), Weave (protocol), Live CD, LAN Manager, Apple Lisa, Stardock, Windows NT