function component react js

1function app() {
2    return (
3        <div>   
4            <h1>Hello World</h1>;
5        </div>
6    );
7}

1function Comment(props) {
2  return (
3    <div className="Comment">
4      <div className="UserInfo">
5        <img className="Avatar"
6          src={props.author.avatarUrl}
7          alt={props.author.name}
8        />
9        <div className="UserInfo-name">
10          {props.author.name}
11        </div>
12      </div>
13      <div className="Comment-text">
14        {props.text}
15      </div>
16      <div className="Comment-date">
17        {formatDate(props.date)}
18      </div>
19    </div>
20  );
21}