how to get value of textarea in php

//You use it the same way you would with other $_POST[''] or $_GET[''} Elements
//Give it an ID/Name and then echo $_POST['whateveryounamedit'] / $_GET['whateveryounamedit']; 

<form action="" method="post">
<label>Additional Comments:</label><br>
<textarea cols="35" rows="12" name="whateveryounamedit" id="whateveryounamedit">
<php echo $comments; ?>
</textarea><br>
<input type="submit" name="button" value="Submit"/></form>

<?php

$somevariable= $_POST['whateveryounamedit'];
echo($somevariable);
?>