But gradually a poison disabled personal agency. That poison was the cookie.
Very few web sites in the early web had identity systems. For the peer-to-peer sharing of documents and discovery via embedded links, none were needed. HTTP, the foundational protocol of the web is stateless, meaning the HTTP server does not know whether any two requests are related to each other.
Stateless is fine for document sharing and linking using hypertext. But it makes building a shopping cart really hard. Back in the mid-90’s figuring out how to build a functional shopping cart was on everyone’s mind, mine included. I was the cofounder and CTO of an early ecommerce site, imall.com. Without changing HTTP, the most promising strategy was to include a correlation identifier in all the links generated by the site, so we’d know who was making the request. But this was buggy and caused lots of customer support issues.
A correlation identifier is a unique string that can be used to link requests. Ultimately, the the HTTP community added a correlation identifier called a “cookie” (which took its name from a correlation identifier used in unix
). HTTP cookies are generated by the server and stored on the browser. Whenever the browser makes a request to the server, it sends back the cookie, allowing the server to correlate all requests from that browser.
This is how (simple) ad tracking works. When you see and ad on web site A, it’s being served from a server owned by an ad company that web site A has an agreement with. The ad server plants a cookie in your browser. Now you visit web site B who also serves ads from the same ad server. You browser dutifully reports the ad server cookie back to the ad server along with the information that the ad was on web site B. The company running the ad server now knows you were on web site A and web site B. Rather than correlating requests on a single web site, they are using cookies to correlate your activity across the web.
This is the poison Doc is talking about. The web cookie, as designed, goes well beyond correlating activity on a single web site for purposes of creating some utility like a shopping cart or a chat server. The web cookie allows correlating activities of people across the web. And it doesn’t stop with your browsing history. The ad company starts knowing other things about you (because the web sites you visit tell them) and soon they can develop a comprehensive dossier.