There is sometimes a distinction made between concurrency and parallelism, where "concurrency" just means the programming interface looks parallel but is allowe

There is sometimes a distinction made between concurrency and parallelism, where "concurrency" just means the programming interface looks parallel but is allowed to use out-of-order task-switching under the hood, and "parallelism" is real-deal usage of CPU cores. Both ways of looking at things are useful in different situations.