Before we start learning about React Hooks, we are going to learn about the three fundamental principles of React. These principles allow us to easily write scalable web applications. The fundamental principles are important to know, as they will help us to understand how and why Hooks fit into the React ecosystem.

React is based on three fundamental principles:

• Declarative: Instead of telling React how to do things, we tell it what we want it to do. As a result, we can easily design our applications and React will efficiently update and render just the right components when the data changes. For example, the following code, which duplicates strings in an array is imperative, which is the opposite of declarative:

const input = ['a', 'b', 'c']
let result = []
for (let i = 0; i < input.length; i++) {
    result.push(input[i] +...