An Operating system is a program that provides an interface between computers and its users.
An important aspect of operating systems is that it manages various tasks quite efficiently.
It's used in wide variety of fields - like an operating system in personal computer is used for business applications, gaming, for organising things, carrying out tons of online tasks, and much more. Nowadays, users can also interface easily with the computer using handheld operating system like Android. Simply put, an operating system provides efficiency, convenience, and flexibility.