n.
Mode of computer operation in which the computer works on multiple tasks at the same time.
A task is a computer program (or part of a program) that can be run as a separate entity. On a single-processor system, the CPU can perform preemptive (also called time slicing or time sharing) multitasking, where it executes part of one program, then switches to another program, and then returns to the first one. On multiprocessing systems, each processor can handle a separate task.