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

Beacon Software, an AI holding company, raised a $225 million Series C round to acquire software companies and enhance its AI operating system.

From The Wall Street Journal • Jun. 9, 2026

"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

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 airline struggled more than rivals after the CrowdStrike outage two summers ago crashed millions of computers around the world running Microsoft’s Windows operating system.

From The Wall Street Journal • May 26, 2026

Then he would come out of it, and the two would go out to dinner, then plunge into writing some program or into a long battle over which operating system was superior.

From "Geeks: How Two Lost Boys Rode the Internet Out of Idaho" by Jon Katz