An operating system is the core software layer that manages hardware and provides the environment for apps to run.
If someone does not know what the operating system is, almost every later word like file, process, service, or permission becomes blurry.
The operating system is the main software that sits between the hardware and the apps. It manages files, memory, devices, users, and running programs.
The operating system is the boss software that helps the computer parts and apps work together.
The operating system is not just the desktop you click on. It is the deeper software layer that controls how the machine runs and how programs use the machine safely.
When you understand the operating system, later lessons about files, users, networking, and troubleshooting stop feeling like unrelated tricks.
Study the larger concept after the word itself becomes clear.