ReactOS

ReactOS is an open source operating system by the ReactOS Foundation. Unlike Unix-like operating systems, ReactOS re-implements the NT architecture and Windows API as a standalone OS. Its goal is to reach program and driver compatibility with Windows. As of 2023, the support level is on par with Windows Server 2003 SP2. The latest version is currently 0.4.14.
It's rarely used in OSM Community.
== Development ==
In 1996, a group formed under the name FreeWin95, with the intention of making an open source Windows 95 clone. Development on FreeWin95 halted soon after Windows 98 was released, as source code contributions never materialized. After a short hiatus, the group reformed in 1998 and changed the project's name to ReactOS. Most development is made gradually, with releases set every 2-6 months. A version number is assigned to major releases (such as 0.4.14), while nightly builds and source code builds use their commit number instead.
== Current state ==
ReactOS is still considered alpha-quality software and only recommended for evaluation and testing purposes. Installation, hardware detection, booting, and running programs can suffer from bugs. As the operating system is open source, it can be freely built from source code, or downloaded from the nightly builds website.
Virtualization support exists for QEMU, however, it can run on other hypervisors. It's possible to install ReactOS on a physical machine, however, this configuration can be risky.
== Release history==
System version	Release date	Release information
0.2.0 	2004-01-25 	First release with working GUI
0.2.1 	2004-03-03 	Bug fixes only
0.2.2 	2004-04-27 	Bug fixes only
0.2.3 	2004-06-26 	New LiveCD image, improved stability in the kernel and win32k, networking improvements and improved shell, command prompt and hardware drivers
0.2.4 	2004-09-13 	Code synced with Wine, compiler fixes and cleaned up file headers
0.2.5 	2005-01-02 	Imported Notepad from WINE, added Date/Time application
0.2.6 	2005-04-09 	NVIDIA OpenGL hardware acceleration works, NCITool created for generating system call database files
0.2.7 	2005-08-21 	New Command Prompt, My Computer and ReactOS logo icons, improved first-stage installer appearance
0.2.8 	2005-10-29 	VMware detection, CSRSS rewrite
0.2.9 	2005-12-22 	Bug fixes only
0.3.0 	2006-08-27 	First version to officially support networking
0.3.1 	2007-03-10 	Program manager included, start of kernel rewrite
0.3.2 	skipped 	Branch created but never released
0.3.3 	2007-09-12 	Kernel and win32k improvements
0.3.4 	2008-01-22 	Registry support rewrite, remote desktop client and Plug and Play
0.3.5 	2008-06-30 	Bug fixes only
0.3.6 	2008-08-06 	RTL support
0.3.7 	2008-11-04 	Improved x86-64; MSVC, new stacks
0.3.8 	2009-02-04 	Introduced PSEH and multi-partition HDD support in LiveCD
0.3.9 	2009-04-26 	24 MB minimum RAM, faster hyperspace mapping, initial sound support
0.3.10 	2009-07-05 	Initial SATA support, USB keyboard/mouse support, Paint clone, initial MSVC.
0.3.11 	2009-12-16 	Kdcom rewrite; Chinese/Korean fonts; compatibility updates; sound system improvements
0.3.12 	2010-10-20 	Trap handler rewrite; timer and message handling rewrite; NMI support; SxS support; partial EMS support
0.3.13 	2011-03-22 	Heap manager rewrite, improved SATA support, fixed graphics issues
0.3.14 	2012-02-07 	ACPI enabled by default, WiFi support (unencrypted and WEP), theme support, new TCP/IP driver (LwIP), MSVC compatibility, Scatter/Gather DMA operations supported, shell32 rewrite
0.3.15 	2013-05-30 	USB support for mice, keyboard, and storage devices; rewritten session management; AHCI support with updated UniATA driver; alternate ReactOS Memory Management Module has taken over all memory management responsibilities except for sections; preliminary support for debugging ReactOS components using WinDbg; improvements based on results from the AutoHotkey application functionality test suite; Bugfixes based on running Driver Verifier on several bundled drivers
0.3.16 	2014-02-06 	CSRSS rewrite; theme support improved; network card driver for the RTL8139, allowing ReactOS to support newer versions of QEMU out of the box
0.3.17 	2014-11-05 	Inclusion of an NTVDM; font improvements; bug fixes
0.4.0 	2016-02-16 	Improved USB support, new file explorer shell and theming, improved VirtualBox and Virtual PC support, ext2 read/write support, NTFS read support and improved networking support
0.4.1 	2016-05-17 	Improved Activation Context, Btrfs support, improved Shell, USB bug fixes, support for Virtual Machine Shared Folders
0.4.2 	2016-08-16 	Improved Btrfs and extended file system support, ReiserFS and UFS/FFS, introduced .NET Framework 2.0 and 4.0 support, Shell fixes and improvements
0.4.3 	2016-11-16 	New Winsock library, initial sections support, usual bug fixes
0.4.4 	2017-02-16 	Initial print stack support, minor font fixes, usual improvements and bug fixes
0.4.5 	2017-05-18 	Improved rendering of fonts and font metrics, major fixes in kernel and drivers, Microsoft Office 2010 tested as functioning
0.4.6 	2017-09-01 	Several fixes for dual-boot issues, improved theming support, NFS driver added, several kernel and filesystem fixes
0.4.7 	2017-12-06 	Improved version of the applications manager RAPPS, implementation of the "Quick-Launch" toolbar in the explorer; various bug fixes in the filesystem drivers, improvements in the RDBSS/RXCE and NFS support.
0.4.8 	2018-04-14 	Balloon notifications, notification tray, shell autocompletion, a new NTFS driver, crash dump reporting and experimental support for NT6+ software.
0.4.9 	2018-07-23 	ReactOS is (again) self-hosting.
0.4.10 	2018-11-06 	Supports BTRFS booting.
0.4.11 	2019-03-04 	Drivers for battery management (its icon is located in the taskbar, in the bottom right of the screen, next to the clock). Support for updating an existing ReactOS installation. Improved SATA support.
0.4.12 	2019-09-23 	Kernel improvements, window-snapping feature, font improvements, Intel e1000 NIC driver, user-mode DLLs, new themes.
0.4.13 	2020-04-09 	New USB stack, FAT driver from FreeLoader optimized, new software introduced: Accessibility Utility Manager.
Category:Real operating system