jQuery fadeIn function

html file for fadeIn function:

<html lang="en-US">

<head>

<meta charset="UTF-8">

<title>Learn & Do</title>

<script type="text/javascript" src="jquery.js"></script>

<script type="text/javascript" src="fadein.js"></script>

<style type="text/css">

.first

{

width:300px;

height:200px;

background:red;

}

</style>

</head>

<body>

<input type="button" value="fadein" id="fade"  />

<div class="first"></div>

</body>

</html>

...................................................................................................................................................................

jQuery (.js) file of fadeIn function:

$(document).ready(function(){

$('#fade').click(function(){

$('.first').fadeIn(4000);

});

});