I used equally spaced partitions because it made things a little bit conceptually simpler. And this right here is a picture of the person that Riemann sums was named after. This is Bernard Riemann. And he made many contributions to mathematics. But what he's most known for, at least if you're taking a first year calculus course, is the Riemann sum and how this is used to define the Riemann integral. Both Newton and Leibniz had come up with the idea of the integral when they had formulated calculus. But the Riemann integral is kind of the most mainstream formal or I would say rigorous definition of what an integral is.