What is differentiation used for in the real world?

Differentiation is very helpful in the real world, in many different fields. In terms of business and economics, being able to derive maximum and minimum values of certain functions can prove extremely useful for firms, such as figuring out profits and costs. You can also compute the marginal revenues/costs that you should expect to make/incur at any given point in time in a certain setting.

Differentiation also allows us to compute rates. In Biology, the ability to calculate birth rates and death rates given a graph or certain information is vital for studies and allows for comparisons and scientific developments to be made.