ReactOS is an open-source project aimed at providing a free and compatible replacement for Windows, eliminating unwanted features like telemetry and advertisements. The latest update, ReactOS 0.4.15, is the first major release in over three years and includes enhancements such as Plug and Play fixes, audio improvements, memory management tweaks, registry healing, and upgrades to essential tools like Notepad and Paint. This version has nearly eight times the number of commits compared to 0.4.14. Future plans for ReactOS include UEFI support, symmetric multiprocessing, a new graphical installer, a new NTFS filesystem driver, power management capabilities, and support for newer applications. ReactOS 0.4.15 is available for download.