The operating system of the TV box is the software used to operate it. The overwhelming majority use Android, just like most mobile phones.
Android: Provides access to the Google Play Store for a wide range of applications such as YouTube, Netflix, Spotify, etc.
Linux: It is mainly used in custom firmware, TV Boxes oriented towards Kodi, or streaming devices that do not require full Android functionality. It usually has fewer available applications but offers high performance and security.
tvOS (Apple): Provides a smooth user experience, full integration with Apple services (AirPlay, Apple Arcade, Siri), and a secure, closed ecosystem. Supports only apps approved in the App Store, ensuring stability and security.