ReactOS is a free and open-source operating system for x86/x64 personal computers intended to be binary-compatible with computer programs and devices. Developed by Aleksey Bragin
License: Open Source
ReactOS is an open-source operating system designed for compatibility with Windows applications, making it suitable for users looking for a free alternative to Windows. In contrast, CentOS is a robust, enterprise-level Linux distribution focused on stability and security, primarily used for server environments.