Alternative to HTTP Cookies?

Question

They say Cookies are bad. I personally believe there should be a "smarter" way to detect the state of a user on a web app.

Say, currently this is how it works i

Answer 1

One of the Fundamental principals of REST, and I mean real REST is not to store state on the server, if there is no state on the server, then there is no need for a cookie to be used as a key to look that state up.