게양이란 무엇입니까 ??

a variable can be used before it has been declared because it stores in memory

💎 기능

b();

function b(){
  console.log('foo');
}

// "foo" 
// ✅ thanks to hoisting, function has stored in memory before declaring

arrFn();

const arrFn = () => {
  console.log('arrow!!');
}

// 🔥 Uncaught ReferenceError: Cannot access 'arrFn' before initialization

💎 변수

console.log(b)
var b  = 10;

// "undefined"
// ✅ default initialization of the var is undefined.
// ❗ initial value = undefined

console.log(NAME) // 🔥 Throws ReferenceError exception as the variable value is uninitialized
const NAME = 'kaziu'

console.log(count) // 🔥 Throws ReferenceError exception as the variable value is uninitialized
let count = 2