Setting cookies, is relatively simple, using the following code:
setcookie("cookiename", $cookie_val, time() + 3600, "", "");
Note: You should set all the above parameters to ensure that the cookie gets written in Internet Explorer 5+. Also, the PHP manual mentions another cookie for secure connections as an additional parameter. For some reason, setting this parameter causes the cookie not to be written to IE 5+, so be sure not to set it.
To retrieve the cookie, use the following:
$HTTP_COOKIE_VARS["cookiename"]
To delete the cookie:
// set the cookie expiry date to some time in the past
setcookie ("cookiename", "", time() - 3600, "", "");