How to display random Qutes using Javascript?

Hi.
I would like to display random text on my webpage, and I have found a scrpict for it looking like this:

<script language="JavaScript">
<!--
var r_text = new Array ();
r_text[0] = "All the leaves are brown";
r_text[1] = "And the sky is grey";
r_text[2] = "I've been for a walk";
r_text[3] = "On a winter's day";
r_text[4] = "I'd be safe and warm";
r_text[5] = "If I was in L.A.";
r_text[6] = "California dreaming, On such a winter's day";
var i = Math.floor(7*Math.random())

document.write(r_text[i]);

//-->
</script>

I have no experience using Javascripts, so my question is how to I do it?