Redux is built on three main building blocks:

1. Actions
   Actions are plain JavaScript objects that describe what happened.
   Example:

   { type: 'INCREMENT' }

2. Reducers
   Reducers are pure functions that take the current state and an action as arguments and return a new state.
   Example:

   function counterReducer(state = 0, action) {
     switch (action.type) {
       case 'INCREMENT':
         return state + 1;
       case 'DECREMENT':
         return state - 1;
       default:
         return state;
     }
   }

3. Store
   The store holds the application state. It brings Actions and Reducers together.
   It provides methods like dispatch(action), getState(), and subscribe(listener).

These three pieces work together in a unidirectional flow to manage state consistently across your app.

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