Store. A single function, the
reducer, is responsible for making modifications to the Store. We trigger the reducer by 'dispatching' an
action - a JS object that describes how our data should change. The reducer function receives the action as an argument and makes changes accordingly. Other parts of the code (usually React Components) can subscribe to data in the Store. When data changes, Redux notifies subscribers of the change.
One of the most consolidated misconceptions about programming, since the early days, is the idea that such activity is purely technical, completely exact in nature, like Math and Physics. Computation is exact, but programming is not.