The operating system refers to the computer programs used to manage and control the computer hardware and software resources, which are directly run on the computer as the most basic system software—all the other software runs on top of the operating system. Mobile operating system refers to the operating system running on mobile phones, PADs, and smart TVs. Google's Android and Apple's iOS both belong to the mobile operating system. An embedded system is a computer system that is fully embedded on a device or inside a device and is designed to meet specific needs, such as the common embedded system in daily life, including TV set-top boxes, routers, refrigerators, microwave ovens, mobile phones, etc. Similar to embedded systems, there are certain computing units in real-time systems that can anticipate the environment of the system and its internal applications, which is the determinism that many of the real-time system books have mentioned.