"Concurrent Means Parallel"
This video presents the same text shown beside it, spoken and on screen. It adds nothing the text does not say.
State
Concurrency on a single processor is not parallelism — the machine alternates between tasks, sharing one resource by turns, which costs efficiency that true parallelism keeps.
Show
One clerk juggling two shop counters serves both, slower than two clerks would.
Watch for
Alternation resembles simultaneity from far enough away.