State management in Web applications is a contentious issue. Should you store user data per session or should you persist it across sessions? You can easily store information temporarily while someone navigates your site by using session state. That’s typically an in-memory data store indexed by a unique session key assigned to each new user and that lasts only for the duration of the "session" with the client. Storing information across sessions is typically done by building your own back-end data store indexed by some user identifier (typically obtained after a user logs onto the site).