What are the key functions of a modern operating system?

The key functions of a modern operating system are managing hardware, software resources, and providing various services for user applications.

An operating system (OS) is a crucial component of any computer system. It acts as an intermediary between the user and the computer hardware, managing and controlling the execution of all kinds of programs. The OS is responsible for managing hardware resources such as the CPU, memory, storage devices, and input/output devices. It allocates these resources to different software applications as needed, ensuring that all applications can run smoothly and efficiently.

One of the primary functions of an OS is process management. This involves keeping track of all the processes running on the system, deciding which process gets the CPU when, and managing the allocation and deallocation of memory for these processes. The OS also handles process synchronisation and communication, ensuring that processes can work together without interfering with each other.

Another key function of an OS is file management. The OS is responsible for organising files on the storage devices, keeping track of which blocks of storage hold which files, and managing access to these files. It also provides a file system interface for user applications, allowing them to read and write files in a way that is independent of the specific type of storage device being used.

The OS also manages the system's input and output devices, such as keyboards, mice, printers, and displays. It provides a consistent interface for these devices, allowing user applications to interact with them in a standard way, regardless of the specific type of device being used.

In addition to these hardware and software management tasks, the OS also provides a range of services for user applications. These include services for managing user interfaces, network communication, security, and more. These services are typically provided through a set of system calls, which are programming interfaces that allow user applications to request services from the OS.

In summary, the operating system plays a vital role in the functioning of a computer system. It manages and coordinates the use of the hardware and software resources, and provides a range of services that make it easier for user applications to perform their tasks.