operating system

apparatus which enables the operation of a device; main program in a computer which is responsible for the allocation of resources to its various procedures

An operating system (OS) is the software that manages the sharing of the resources of a computer. An operating system processes system data and user input, and responds by allocating and managing tasks and internal system resources as a service to users and programs of the system. At the foundation of all system software, an operating system performs basic tasks such as controlling and allocating memory, prioritizing system requests, controlling input and output devices, facilitating networking and managing file systems. Most operating systems come with an application that provides a user interface for managing the operating system, such as a command line interpreter or graphical user interface. The operating system forms a platform for other system software and for application software. Linux and Mac OS (or any other BSD-derivative) are popular UNIX-like operating systems.
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Noun
1. (computer science) software that controls the execution of computer programs and may provide various services
(synonym) OS
(hypernym) software, software system, software package, package
(hyponym) DOS, disk operating system
(part-holonym) platform
(part-meronym) supervisory program, supervisor, executive program
(classification) computer science, computing

An integrated collection of routines that service the sequencing and processing of programs by a computer. Note: An operating system may provide many services, such as resource allocation, scheduling, input/output control, and data management. Although operating systems are predominantly software, partial or complete hardware implementations may be made in the form of firmware. (188 )

<operating system> (OS) The low-level software which handles the interface to peripheral hardware, schedules tasks, allocates storage, and presents a default interface to