operating system

American  

[op-uh-rey-ting sis-tuhm] / ˈɒp ə reɪ tɪŋ ˌsɪs təm /

noun

Computers.

1. the collection of software that directs a computer's operations, controlling and scheduling the execution of other programs, and managing storage, input/output, and communication resources. OS

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operating system British  

noun

1. the set of software that controls the overall operation of a computer system, typically by performing such tasks as memory allocation, job scheduling, and input/output control

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operating system Scientific  

/ ŏp′ə-rā′tĭng /

1. Software designed to handle basic elements of computer operation, such as sending instructions to hardware devices like disk drives and computer screens, and allocating system resources such as memory to different software applications being run. Given uniformly designed operating systems that run on many different computers, developers of software do not need to concern themselves with these problems, and are provided with a standard platform for new programs.

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operating system Cultural  

1. The software that allows computer users to run applications with the hardware of a specific system. Microsoft® Windows® or Apple® Computer's OS are examples of operating systems.

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Etymology

Origin of operating system

First recorded in 1960–65

Example Sentences

"Legislation could cover operating system providers and others in the supply chain, such as retailers, and will not affect the use of devices owned and used by adults who verify their age," he said.

From BBC • Jun. 8, 2026

Apple deftly made the transition to Arm Macs because it controlled every part of the product: The chip, the device, the operating system, many of the apps, and the developer tools.

From Barron's • Jun. 2, 2026

IBM’s own guidance suggested that 10% growth is likely the ceiling through 2026, largely due to slowing demand for its core product, the Red Hat Enterprise Linux operating system.

From Barron's • Jun. 1, 2026

The operating system stayed embedded in retail, banking, healthcare, energy, law enforcement and defense systems long after it should have been retired.

From MarketWatch • May 27, 2026

The first version of the Windows operating system launched in 1985, and the breakthrough version that made IBM PCs much more user-friendly—Windows 3.0—shipped on May 22, 1990, only six months after the wall went down.

From "The World Is Flat" by Thomas L. Friedman