const user = {
    name: "철수",
    age: 30
}

for (let key in user) {
  console.log(key, ":", user[key]);  
}
/*
    출력:
    "name" : "철수"
    "age" : 30
*/
<ul>
    <li>김밥</li>
    <li>라면</li>
    <li>떡볶이</li>
</ul>
const liElements = document.querySelectorAll("li"); // li 선택자를 모두 선택
console.log(liElements); // NodeList(3) [li, li, li]

/* for...of 문 적용 */
for (const liElement of liElements) {
    console.log(liElement.textContent);
}
// 출력: "김밥" "라면" "떡볶이"