Air or water or any other fluid can flow smoothly sometimes. You can turn on a faucet a little bit and the water will stabilize into a steady stream. It might even look like it isn’t moving, even though it is. This is sometimes called “laminar” flow, and it is the opposite of turbulent flow.
Sometimes the flow is not so smooth. When the water(or air) goes too fast(or bumps into some other air going in a different direction), some of it stops going straight and makes little swirls, which make other little swirls, and and the whole thing becomes a chaotic mess. The fluid is still moving, but it wastes a lot of energy making chaotic little swirls. Additionally, if you’re an airplane or something that relies on air, those swirls going in different directions can be very bumpy.
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