Final answer:
An operating system is a collection of programs critical for managing computer activities and facilitating human-software interactions, from managing microprocessors to supporting complex decision-making processes with various applications.
Step-by-step explanation:
A operating system (OS) is a collection of programs that manages and coordinates computer activities. It is the most critical piece of software installed on the computer. The operating system functions at several levels including the physical level, where it manages electronic changes, the design level, where it interprets the programmer’s commands, and the commonsense level, which users interact with for tasks like word processing or solving equations. The OS is responsible for managing the computer's microprocessor, which is an integrated circuit that implements the computer processor functionalities and can store and manipulate data to perform a variety of functions. Additionally, the operating system facilitates human-software interactions, particularly by aiding the decision-making processes of individuals as they interact with complex automated systems and use various applications such as data base user interface and query software, email software, office suite software, and spreadsheet software.