Operating systems concept: What is the name of the technique in which the operating system executes multiple programs seemingly at the same time by rapidly switching the CPU among them?

Introduction / Context:
Modern operating systems manage numerous concurrent activities. Even on a single CPU, users experience simultaneity because the OS slices time and shares processor resources across tasks. This foundational concept underpins responsiveness and throughput.

Given Data / Assumptions:

• Single or multi-core CPU environment.
• Goal is to run several programs “at once.”
• Time slicing and context switching are available.

Concept / Approach:

Multitasking schedules processes or threads using a dispatcher that performs context switches. With preemptive multitasking, the scheduler interrupts tasks to enforce fairness and latency bounds. Cooperative multitasking relies on tasks yielding control. Either way, rapid switching creates the illusion of parallelism on single-core systems.

Step-by-Step Solution:

Verification / Alternative check:

OS textbooks describe round-robin, priority, and multilevel feedback queues as standard multitasking schedulers that time-slice CPU access among runnable tasks.

Why Other Options Are Wrong:

• Partitioning: divides memory or disks; not CPU time sharing.
• Windowing: user-interface metaphor, not scheduling.
• Paging: virtual memory mechanism; unrelated to CPU task switching directly.

Common Pitfalls:

Confusing multithreading (within a process) with multitasking (across processes); conflating paging with swapping; assuming true parallelism requires multiple cores (time slicing suffices for perceived concurrency).

Final Answer:

Multitasking