An operating system (OS) is the software that manages the hardware and software resources of a computer. It acts as an intermediary between the computer hardware and the applications that run on the computer. The operating system provides the necessary support and services to run applications, manage memory, handle input/output operations, and perform other tasks. It is the first software that is loaded when the computer starts up, and it runs continuously in the background, providing the necessary resources and services to other programs. Examples of popular operating systems include Windows, macOS, Linux, and Android. The basic functions of an operating system include:
Managing files: An operating system is responsible for managing the file system, organizing files and directories, and providing access to files for both the user and the applications running on the computer. Handling interrupts: The operating system is responsible for handling interrupts generated by hardware components, such as the keyboard or mouse, and ensuring that the computer responds in a timely manner. Providing an interface: The operating system provides a user interface, such as a graphical user interface or command-line interface, allowing the user to interact with the computer and perform tasks. Managing peripherals and drivers: The operating system manages peripheral devices, such as printers and storage devices, and provides drivers to allow the hardware to interact with the software. A graphical user interface (GUI) is a type of user interface that uses graphical elements, such as icons and windows, to allow the user to interact with the computer. A command-line interface (CLI) is a type of user interface that uses text-based commands to perform tasks and access information. A GUI is more user-friendly and easier to use than a CLI, but a CLI provides more control and is more efficient for advanced users. Managing memory: The operating system manages the computer's memory, allocating memory to running applications and managing memory allocation and deallocation as needed. The operating system uses various algorithms, such as first-fit and best-fit, to determine how to allocate memory to running applications, and it also manages the freeing up of memory when applications are closed. Managing multitasking: The operating system is responsible for managing multitasking, allowing multiple applications to run simultaneously and switching between them as needed. Providing a platform for running applications: The operating system provides a platform for running applications, providing the underlying support and resources needed to run the software. Providing system security: The operating system provides security features, such as user authentication, access control, and data encryption, to protect the computer and its data from unauthorized access and attack. The operating system also provides firewalls, antivirus software, and other security tools to prevent unauthorized access and protect against attacks. Managing user accounts: The operating system is responsible for managing user accounts, allowing multiple users to log in and use the computer and managing the permissions and access rights for each user.