What is an operating system?

An operating system is system software that is essential for managing a computer's hardware and software resources. It acts as an intermediary between users and the computer hardware. The operating system controls the execution of programs, manages system memory, handles input and output devices, and ensures that all hardware components work in harmony to provide a functioning environment for applications.

This software is responsible for multitasking, permitting multiple processes to run simultaneously while managing allocation of resources like CPU time and memory space. Additionally, it includes user interface elements, such as command-line shells or graphical user interfaces, that allow users to interact with the computer effectively.

In contrast, the other options do not accurately define an operating system. The hardware configuration pertains to the physical components of a computer, while productivity applications are designed to perform specific tasks or functions, rather than manage hardware. Finally, the storage medium refers to devices that store data, like hard drives or SSDs, rather than a software layer that enables interaction with those storage devices.