ReactOS is an advanced, free, and open-source operating system providing a ground-up implementation of Windows NT compatible operating system.

It aims to achieve complete binary compatibility with applications and device drivers meant for NT and XP operating systems by using a similar architecture and providing a complete and equivalent public interface.

ReactOS is a great example of an almost complete working model of a Windows-like operating system available at this time. Consequently, working programmers will learn a great deal by studying the source code and participating in development.

In short, ReactOS aims to run your applications and use your hardware, a free operating system for everyone.

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