30 years ago, Lou Montulli set out to solve a fundamental problem with the internet, and accidentally created an entirely different one. On today's show, how the cookie went from an obscure piece of code designed to protect anonymity, to an online advertiser's dream, to a privacy advocate's nightmare.Subscribe to Planet Money+ in Apple Podcasts or at plus.npr.org/planetmoneyLearn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy