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