We know FP matters, but what is it really? There are a lot of discussions related to FP superiority and different definitions of it, but simply, it is a style of programming that models computations as the evaluation of expressions or declarations. FP is a declarative programming style, as opposed to OOP, which is categorized as imperative programming.
Theoretically, FP employs the concepts of category theory, which is a branch of mathematics. It is not necessary to know the category theory to be able to program functionally, but studying it will help to grasp some of the more advanced concepts, such as Functors, Applicative Functors, and Monads. We will get into category theory and its relationship with FP later, so for now, ...
