Why do we need air resistance?

Question

Why do we need air resistance? Why is it important?

Answer 1

It's beneficial in some activities, harmful in others. A parachutist needs air resistance. It forces us to use considerable energy in travel. Cars are designed to minimize air resistance to maximize fuel economy.

It's a fact of our world. We make use of it when we can. Tolerate it, and/or minimize it, when its effect is negative.