Redux

Reference:

https://redux.js.org/tutorials/essentials/part-1-overview-concepts

Redux is a pattern and library for managing and updating application state, using events called "actions". It serves as a centralized store for state that needs to be used across your entire application, with rules ensuring that the state can only be updated in a predictable fashion.

Redux is more useful when:

• You have large amounts of application state that are needed in many places in the app
• The app state is updated frequently over time
• The logic to update that state may be complex
• The app has a medium or large-sized codebase, and might be worked on by many people

Not all apps need Redux.

type and payload in Redux:

Payload is what is keyed ( the key value pairs ) in your actions and passed around between reducers in your redux application. For example -

const someAction = {
  type: "Test",
  payload: {user: "Test User", age: 25},
}

This is a generally accepted convention to have a type and a payload for an action. The payload can be any valid JS type ( array , object, etc ).

Reference:

https://stackoverflow.com/questions/51357412/what-is-a-payload-in-redux-context