PHP Example
Screen shot
Screen shot
Screen shot
PHP Script to use of hidden field and isset() function.

<html>
<head>
</head>
<body>
<table border="1" width="100%">
<tr>
<td width="20%">
<?php
if(isset($_POST['btn']))
echo "Step 2";
elseif(isset($_POST['btn2']))
echo "Step 3";
else
echo "Step 1";
?>
</td>
<td width="80%" rowspan="3">
<?php
if(isset($_POST['btn']))
{
?>
<form name="frm" action="" method="post">
Enter City<input name="city" type="text"><br>
Enter Country<input name="country" type="text"><br>
<input name="fname" type="hidden" value="<?php echo $_POST['fname']; ?>" /><br>
<input name="age" type="hidden" value="<?php echo $_POST['age']; ?>" />
<input name="btn2" type="submit" value="submit">
</form>
<?php
}elseif(isset($_POST['btn2']))
{
echo "Your Name : ".$_POST['fname']."<br>";
echo "Your Age : ".$_POST['age']."<br>";
echo "Your City : ".$_POST['city']."<br>";
echo "Your Country : ".$_POST['country']."<br>";
}
else
{
?>
<form name="frm" action="" method="post">
Enter Name<input name="fname" type="text"><br>
Enter Age<input name="age" type="text"><br>
<input name="btn" type="submit" value="Next">
</form>
<?php
}
?>
</td>
</tr>
</table>
</body>
</html>

You can download source code here