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

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

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