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
Gentoo is a highly customizable Linux distribution aimed at advanced users who appreciate optimization and control, while ReactOS is an open-source operating system designed to be compatible with Windows applications, targeting users who want a familiar Windows-like environment. Gentoo's rolling release model gives it a performance edge, but its steep learning curve may deter casual users, whereas ReactOS offers a more user-friendly experience but lacks full compatibility with modern software.