echo "<form action='chatbox.php' method='get'>";
echo "Name: <input type='text' name='visName' size=15><br>";
echo "Message: <input type='text' name='message' size = 15><br>";
echo "<input type='submit' value='Post' name='post'><br>";
echo "</form>";


CHATBOX.PHP

if(isset($post))
{
    if(file_exists('chatbox.txt'))
    {
         $fileId = fopen('chatbox.txt', 'a');
         fputs($fileId, $_POST['visName']);
         fputs($fileId, $_POST['message']);
         fclose($fileId);
    }
    else
    {
         $fileId = fopen('chatbox.txt', 'w');
         fputs($fileId, $_POST['visName']);
         fputs($fileId, $_POST['message']);
         fclose($fileId);
    }
}

$fileId = fopen('chatbox.txt', 'r');
while(!feof($fileId))
{
    $text = fgets($fileId);
    echo "<table>";
    echo "<tr><td>".$text."</td></tr>";
    echo "</table>";
}
fclose($fileId);