Which OS feature allows more than one application to run at a time?

Which OS feature allows more than one application to run at a time?

• A. Scheduling
• B. Multitasking
• C. Multithreading
• D. Virtualization

Answer: (B)

Multitasking is the ability of an operating system to run more than one application at once by rapidly switching the CPU between programs. The system uses scheduling to decide which program gets to run next and for how long, performing context switches so each program saves its state and resumes later. This time-sharing gives the user the impression that multiple apps run simultaneously, even on a single-core processor. Scheduling is the mechanism that determines the order and duration of each program’s use of the CPU, and is essential to multitasking, but the feature itself is multitasking. Multithreading concerns multiple threads within a single program, which can improve responsiveness or performance inside that app, but it doesn’t by itself enable running separate applications at the same time. Virtualization creates separate virtual machines, each potentially running its own OS and apps, which is broader than the basic capability of an OS to run several applications concurrently.

Multitasking is the ability of an operating system to run more than one application at once by rapidly switching the CPU between programs. The system uses scheduling to decide which program gets to run next and for how long, performing context switches so each program saves its state and resumes later. This time-sharing gives the user the impression that multiple apps run simultaneously, even on a single-core processor.

Scheduling is the mechanism that determines the order and duration of each program’s use of the CPU, and is essential to multitasking, but the feature itself is multitasking. Multithreading concerns multiple threads within a single program, which can improve responsiveness or performance inside that app, but it doesn’t by itself enable running separate applications at the same time. Virtualization creates separate virtual machines, each potentially running its own OS and apps, which is broader than the basic capability of an OS to run several applications concurrently.