Show alert by click (msg box)

<!-- this script got from www.javascriptfreecode.com-Coded by: Krishna Eydatoula --></span></div><span class="Apple-style-span" style="font-family: tahoma; font-size: 11px; white-space: pre-wrap; "> <!-- Start of Message Alert --> <!-- Use this button in a form to pop-up a message when the user clicks it --> <form> <input type="button" value="message" onclick="alert('YOUR MESSAGE GOES HERE'); return true"> </form> <!-- End of Message Alert --> <span style="font-family:Tahoma;"><a target="_blank" href="http://www.javascriptfreecode.com/"><span style="font-size: 8pt; text-decoration: none">JavaScript Free Code</span></a></span>