Side Effect ( after the initial render)

Act upon property updates

useEffect is similar to :

componentDidMount, componentDidUpdate, and componentWillUnmount

import { useEffect } from 'react';


function MyComponent(props) {
	// ...

	useEffect(() => {
		const { subscribe } = props.store;
		const unsubscribe = subscribe(...);
		return unsubscribe
	}, []);

	return 
}

Act up on a state change

useState

Used to store state for a functional component