The answer is "yes". The problem is that the web isn't stateful, as we term it, so each request you make is a totally blank slate—except for cookies. If they d

The answer is "yes". The problem is that the web isn't stateful, as we term it, so each request you make is a totally blank slate—except for cookies. If they do any expensive computations and then cache them in the session (temporary data associated with your browser through a cookie) clearing your cookies will force them to do it again. In my experience it's better to trust 1st-party cookies that the site you're visiting directly may set, rather than trusting all 3rd party cookies set by folks like Google or Facebook. A simple example is that you indicated some preference. The only way for the browser and server to retain that preference is via a cookie.