State management with Redux

As mentioned, Redux uses a single store to manage the state of the application. Apart from Store, there are two other building blocks: Actions and Reducers.

Let's take a look at how these building blocks help maintain state and update the view when state in Store changes.

Actions

Actions let you define the operations that the user can perform to update the state of the application. An Action is a JavaScript object of the { type, payload } shape, where type is a string mentioning the user action and payload is the data with which the state should be updated:

let todoId = 0;
export const addTodo = text => ({
    type: 'ADD_TODO'
    payload: {
        text,
        id: todoId++,
    ...