Q9Computer Architecture

Pipelining is a technique within a single processor that overlaps the execution of multiple instructions by dividing instruction processing into sequential stages (fetch, decode, execute, write-back), so that while one instruction is being decoded, the next is being fetched, and so on — improving instruction throughput without requiring multiple processing units. Parallelism, by contrast, involves multiple independent processing units (multiple CPUs, cores, or functional units) executing separate instructions or tasks genuinely simultaneously, as in multiprocessor or multicore systems. Pipelining increases throughput by overlapping stages of sequential execution; parallelism increases throughput by genuinely duplicating execution resources.