It's more complicated than that, but the pic could be a decent starting point. Concurrency is the person waiting in the line pulling out their cell phone and ch

It's more complicated than that, but the pic could be a decent starting point. Concurrency is the person waiting in the line pulling out their cell phone and checking their email while they're waiting for their turn at the coffee machine. The get_coffee thread is scheduled, but blocked, so the person waiting is handling the check_email thread. They can only do one thing at a time, but that one thing can swap in and out as situations change.