Monday, March 24, 2008

Privacy Policy

AdSense has recently requested that all publishers using its service now include a privacy policy on their site. I wasn't too thrilled about this at first -- I'm just a blogger, after all. I'm not collecting names, addresses, or Social Security numbers here. I don't know the ages, the genders, or the tastes and preferences of my readers. Why do I need a privacy policy?

I've thought about it a little more now and have decided that a privacy policy isn't such a bad thing to have though I'm not so sure I should be allowed to write one. Google particularly wants users to know about cookies and web beacons and how those two things relate to ads. Cookies and web beacons are two things that people probably don't know enough about, so I'm happy to spread some knowledge around. Quite possibly I'll end up spreading some misinformation as well since I'm not an online privacy expert, but Google AdSense asked for it!

First, let me reiterate what I stated in the first paragraph. I'm not collecting personal information on my visitors. Although web analytics tools exist that could tell me where my visitors come from, what their IP addresses are, and other such information, I'm currently not using any such software with this blog. The only thing I can possibly know about you is what you choose to reveal of yourself via comments or email, and I promise to try to forget any such user-revealed information as soon as possible.

Third party advertisers on this site may be collecting information on you through the use of cookies and web beacons, but you can choose to what extent you wish to allow them to collect this information. Web beacons can take various forms -- some are even images that are too small to be seen -- but their basic use is to collect information on a web user when that user visits a specific site or even reads a particular email: stuff like your IP address, browser of choice, and the time at which you visited the site may be recorded. Cookies are also identifiers, but they can actually be quite useful even for regular users. For instance, shopping sites often use cookies to help keep track of your virtual shopping basket as you add and delete items prior to actually making a purchase. Other sites use cookies to identify returning visitors so that those visitors do not have to manually reenter their login name and password on every visit. As useful as those uses of cookies might be, some companies undoubtedly use cookies along with web beacons largely for their own benefit. Imagine, for instance, that an enterprising sock manufacturer is able to discover that people who click on Mike Gravel ads also have an inordinate fondness for red socks. The potential revenue opportunities would be endless...but do you really want to participate in unpaid market research in that way? And what if there are aspects of your online activities that you'd rather not be linked together? Government web sites can issue cookies as easily as corporate sites can...for that matter, spammers and other online criminals can track you as well! Luckily, all major browsers allow users to disable cookies if they so choose, and many offer more advanced cookie management features (look around the privacy options in your browser to discover these features). Personally, I have my browser set to delete all cookies at the end of each browsing session. This allows me to make use of the features of cookies that I like while I surf, but it prevents me from being tracked on a long-term basis. It's harder to avoid web beacons altogether, but you could at least try surfing behind a proxy to prevent your true IP address from being revealed.

Google AdSense uses the DART cookie to help decide what ads should be shown based on a user's previous web surfing activity. So, for instance, you might tend to visit Democratic-leaning web sites. On this nonpartisan blog, you might get to view Democratic rather than Republican ads because of your past visits whilst a more Republican-leaning surfer might see other ads catered more towards his or her surfing. This might all seem a bit Big Brotherish, but you don't have to let Google tailor ads for you in this way if you find it objectionable -- you can opt out of the program altogether.

More useful information can be discovered via Wikipedia: check out the articles on cookies, web beacons, and proxies to become better informed.