gistfile1.php

<form action="post.php" type="post">
	<input type="text" name="firstname" value="first name" />
	<input type="submit" value="submit">
</form>

<!---on the post.php page -->

<?php echo $_GET['firstname']; ?>

<!--OR if you need some logic-->

<?php 

if (isset($_GET['firstname']) ){
	echo '<p>'.$_GET['firstname'].'</p>';
}
else {
	echo '<p>shit ballz</p>';
}

?>