<!DOCTYPE html>
<html lang="en">
<head>
    <title>Document</title>
</head>
<body>
    <input type="button" id="pure" value="pure" />
    <input type="button" id="jquery" value="jQuery" />
    <script src="https://code.jquery.com/jquery-1.12.4.js"></script>
※ 상기 html 코드를 모든 예제에 적용
var target = document.getElementById('pure');
if(target.addEventListener){
    target.addEventListener('click', function(event){
        alert('pure');
    });
} 
$('#jquery').on('click', function(event){
    alert('jQuery');
})