The Robot Operating System (ROS) is a flexible framework for writing robot software, functioning not as a traditional operating system but as a meta-operating system or middleware that runs on a host OS like Linux. It provides a standardized collection of libraries, tools, and conventions designed to simplify the complex task of creating robust robot behavior across a wide variety of platforms. At its core, ROS offers a message-passing architecture that allows different, independent programs (nodes) to communicate, enabling modular development for tasks such as perception, navigation, and manipulation, while also providing hardware abstraction, package management, and a vast ecosystem of community-contributed software to accelerate robotics research and development.