App.js import { useState } from "react"; const App = () => { const [counter, setCounter] = useState(0); const setCount = () => { setCounter(counter + 1); }; return ( Total clicks : {counter} Click! ); }; export default App; * point 1. jsx 문법 - document.querySelector().innerHTML 대신 {counter} 2. useState import {useState} from 'react'; const [counter, setCounter] = useState(0); - counter : state에 ..