<form action="<?=$PHP_SELF;?>"> <!-- start the form tag -->
<input type="text" name="q" id="q"/> <!-- the input field (we will get data from it later) -->
<input type="submit" value="Get me!"/> <!-- the submit button -->
</form><!-- end the form tag -->
<?php
/* get the value of the field 'q' and store it in $string */
$string = $_REQUEST[q];
/* now print off some text that you can edit and ofcouse the string that will be italics in this example */
print 'You entered the following: <i>' . $string . '</i>';
?>