<link href="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/js/bootstrap.min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<!------ Include the above in your HEAD tag ---------->
<!DOCTYPE html>
<html>
<head>
<title>Save form Data in a Text File using JavaScript</title>
<!--Add few elements to the form-->
<div>
<input type="text" id="txtName" placeholder="Enter your name" />
</div>
<div>
<input type="text" id="txtAge" placeholder="Enter your age" />
</div>
<div>
<input type="text" id="txtEmail" placeholder="Enter your email address" />
</div>
<div>
<select id="selCountry">
<option selected value="">-- Choose the country --</option>
<option value="India">India</option>
<option value="Japan">Japan</option>
<option value="USA">USA</option>
</select>
</div>
<div>
<textarea id="msg" name="msg" placeholder="Write some message ..." style="height:100px"></textarea>
</div>
<div>
<input type="button" id="bt" value="Save data to file" onclick="saveFile()" />
</div>
</div>
</body>
</html>