What's in this cookie?

Do you have a question? Post it now! No Registration Necessary.  Now with pictures!

I'm getting to the part about cookies and setting/getting them and for
grins I wrote this code, expecting to get a null, since this is on
localhost that I created, wrote all the code aand I've never set any

         echo "<br /> <pre>";
         echo "</pre></br />";

Imagine my surprise when I got this back:

     [s_pers] =>  s_nr=1283648608633|1286240608633;
     [mbcc] => 1882B7AD-6552-550F-04A2-EE6FBC03091E

Anyone knows why I would have two cookies set in the $_COOKIE array if
I've never played with cookies on this site before?

When I looked in Firefox's list of cookies, sure enough, these two were
there. Color me puzzled.

Site Timeline