The story of Web cookies, told by their inventor L. Montulli montulli-blog.com/2013/05/the-re… His thoughts on 3rd party cookies montulli-blog.com/2013/05/why-bl…
Great @FiveThirtyEight article on how comScore et al. calculate Web metrics (hint: panels & beacons): fivethirtyeight.com/features/why-w…