| Ubuntu Budgie | — | — | GNU General Public License |
| Ubuntu GNOME | Canonical Ltd. | 2016 | GNU General Public License |
| Ubuntu Server Edition | Canonical Ltd. | 2006 | GNU General Public License |
| Ubuntu Studio | Canonical Ltd., Ubuntu Foundation | 2007 | GNU General Public License |
| UCS@school | Univention | — | GNU Affero General Public License |
| Unity Operating System | — | 2020 | — |
| Uruk GNU/Linux | — | — | — |
| VectorLinux | — | — | — |
| Vitalinux | — | — | — |
| Void Linux | — | 2008 | BSD licenses, free software, ISC license |
| Volumio (music player) | — | — | open-source software, GNU General Public License |
| VyOS | — | — | GNU General Public License, version 2.0 |
| Windows 10 | Microsoft | 2015 | shareware, Microsoft Software Assurance, Azure Dev Tools for Teaching |
| Windows 11 | Microsoft | 2021 | end-user license agreement |
| Windows 12 | Microsoft | — | Microsoft end-user license agreement |
| Windows 7 | Microsoft | 2009 | volume licensing, Microsoft Software Assurance, end-user license agreement |
| Windows 8 | Microsoft | 2012 | end-user license agreement |
| Windows 8.1 | Microsoft | — | end-user license agreement |
| Windows 8.x | Microsoft | 2012 | — |
| Windows NT | Microsoft | 1993 | — |
| Windows Server 2012 | Microsoft | — | end-user license agreement, Client access license, Microsoft Software Assurance, shareware |
| Windows Server 2012 R2 | Microsoft | — | Microsoft Software Assurance, Client access license, shareware |
| Windows Server 2016 | Microsoft | — | end-user license agreement, Microsoft Software Assurance, Client access license |
| Windows Server 2019 | Microsoft | — | — |
| Windows Server 2022 | Microsoft | — | — |
| Windows Server 2025 | Microsoft | 2024 | proprietary license |
| Windows Vista | Microsoft | — | end-user license agreement |
| Windows XP | Microsoft | — | volume licensing, shareware, Microsoft Software Assurance |
| Windows XP Professional x64 Edition | Microsoft | — | volume licensing, commercial software, Microsoft Software Assurance, shareware |
| Winux | — | — | — |
| Xinuos OpenServer | Santa Cruz Operation, Xinuos | — | proprietary license |
| Xubuntu | Canonical Ltd., Ubuntu Foundation | 2006 | — |
| Yanux | Luch Scientific Production Association | — | — |
| YunoHost | — | — | GNU Affero General Public License, version 3.0 |
| Zentyal | — | — | GNU General Public License |
| Zorin OS | Zorin Technology Group Ltd. | 2009 | GNU General Public License |