Unity Simple Comment Component

_Comment.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
/*

    This is a general purpose to add comments for GameObject 

*/
public class _Comment : MonoBehaviour {

    public string comment_0 = "Please Input a comment.";

}

_CommentEditor.cs

using UnityEngine;
using UnityEditor;
using System.Collections;

[CustomEditor(typeof(_Comment))]
public class _CommentEditor : Editor {

    public override void OnInspectorGUI()
    {
        _Comment cmt = (_Comment)target;
        cmt.comment_0 = EditorGUILayout.TextArea(cmt.comment_0);
    }
}