For many people, integration is defined as "the area under the curve" and computed using sets of known rules. Infinite series are a tool we use to reason about

For many people, integration is defined as "the area under the curve" and computed using sets of known rules. Infinite series are a tool we use to reason about calculus concepts more formally. It's a very arbitrary distinction; I was only making it because if you aren't studying calculus in depth you can avoid talking about Taylor polynomials and infinite series, but you can't really avoid talking about derivatives and integrals. If you want to define integrals formally, then you will definitely see infinite series.