“Me want cookies!”   This is what I hear many of my Government clients say – more specifically they want to understand cookies in relation to their web analytics.  I have come to call this the “Cookie Monster” issue since there is so much confusion.  So for my post here (and with many thanks to DJ) I thought Let’s start with dessert first!

Below I have listed from most accurate to less accurate the ways visitors are identified on-line:

1. Authenticated:  The technique by which access to Internet or intranet resources requires the user to enter a username and password as identification.  This is the only way to count visitors “across machines”, as no matter where they log in they are identified correctly.  Cookies are really just tracking unique computers!
2. Persistent Cookies :  A text file containing a random identification string that “lives” on the visitors computer.  Using the value stored in this cookie, WebTrends can identify if you’ve been to the site before and identify you as a “new” or “returning” visitor (but can’t tell anything else about you… it’s a random number after all!).  This is also used to provide “unique visitor” counts in WebTrends.
3. Session Cookies : A text file containing a random identification string that only remains in the computer’s memory for the length of the visit, or “session”.  It does not live on the machine after you navigate away from the site that set it, so there is no way to identify visitors that have been to the site before.
4. IP Address : Internet Protocol Address is used to identify a computer connect to the internet.  Since there are only so many IP addresses to go around, more often than not individual machines end up sharing the same IP address due to the use of proxy servers (used by large organizations like companies and universities), internet service providers or even home wireless routers.

(more…)