01. How to works React State Hook function useState(initiaValue){ var myData = initiaValue; function state(){ return myData; } function setState(newValue){ myData = newValue; } return[state, setState]; } const [data, setData] = useState(0); console.log(data()); //retrun 0 setData(101); console.log(data()); // retrun 101 At first, we are creating a function this name is useState().