An operating system (OS) is a master control program that enables computers and mobile devices to operate. The OS sets the standards that computer applications must follow to work properly, and it manages a broad range of basic functions like memory management, process management, disk storage management, port communication (like Video Graphics Array or Universal Serial Bus) and more. It is also the key to many IT careers, from computer professionals who use OSs in their jobs to IT managers who oversee an entire fleet of computers and smartphones with different operating systems.

The most important task of an OS is to allow all programs that run on a device to function in a flexible, but predictable way. For example, if you had to write a different code for each type of hard drive or Wi-Fi adaptor, your computer would be extremely inflexible. But the OS does this for you. It also provides services like storing information about the location of files on disks or writing low-level routines that enable a graphics program to display an image.

Other functions of an OS include backup and recovery, security features to keep unwanted cyberattackers at bay, disk management, memory management and synchronization. In addition, modern OSs often incorporate advanced features like virtualization technology (allowing multiple instances of the same or different operating systems to run on one machine), cloud-based computing and more. There is also an increased focus on integrating OSs with Internet of Things (IoT) devices to provide unified interfaces and data analytics for diverse smart devices. Operating systems