Quote Originally Posted by davearn
What about tracking cookies? Thay are bad aren't they ?
A cookie is a cookie, is a cookie. By design cookies are readable by the domain that set them, Google cannot read yahoo cookies, etc. But webmasters can insert tidbits of code (usually javascript, but there are other methods) from another domain that may set a cookie. now if this embedded code is used by a number of sites the source domain can now read the cookie no matter what site is loading the code. Is that confusing?

Company A provides a marketing service, to use it you must call a script from their servers. This script sets a cookie from the domain company A controls. usually just some kind of uid in the form of "49485D4B6E650E2476AC5BEEF0004CA9" or the like.

Companies B thru Z subscribe to this service. They embed the code in their sites on all or some of their pages.

John Q. Public (unrelated to company Q in any way) may browse to compay B, D, F, H, and so on. Each page load will trigger the embedded code from Company A. He uses the currency exchange on company D, reads news items on company B's site and so on each visit to those pages with the script the marketing company wil read the cookie it wi have a an ID associaed with it, inless you have filled in some kind fo form with Company A this id is not relaetd to you as a person or your "identity." Company A now can knows that people that use companies B, D, F, H and so on tend to NOT use companies A, C, E and so on and that these intrepid "BDFH" browsers also tend to use (or need) Currency exchange and the news of company B.

This could be equated with the neilsen ratings volunteers allowing there Television viewig habits to be monitored, except you didn't volunteer. If you are a company B, D, F & H website user the marketing company knows that there is one more "BDFH user" Not necessarily WHO that user is. Should you shuffle on over to teenage-ninja-bukake-sluts.org during your browsing experience Company A will have no way of knowing (unless, of course, teenage-ninja-bukake-sluts.org happens to subscribe to Company A's service).

So are "Tracking Cookies" bad? Or do they help related or partner sites improve the "user experience?" Again, cookies don't "do" anything they are just small bits of data to be retrieved when you return to the site that set them. Tracking cookies are not spyware although there are detectors that may identify cookies set by a list of domains as "Tracking Cookies" there is really no way to tell the fucntion of a cookie by it's contents. Cookies are not active, they are passive. Sites like forums or "My Home Page" type sites could not function as smoothly with out them.