title: Authentication for users on a Single Page App?
body: <p>I  have developed a single page app prototype that is using Backbone on the front end and going to consume from a thin RESTful API on the server for it's data.</p>
  
  <p>Coming from heavy server side application development (php and python), I have really enjoyed the new different design approach with a thick client side MVC but am confused on how best to restrict the app to authenticated users who log in.</p>
  
  <p>I prefer to have the app itself behind a login and would also like to implement other types of logins eventually (openid, fb connect, etc) in addition to the site's native login. I am unclear how this is done and have been searching - however unsuccessful in finding information that made it clear to me.</p>
  
  <p>In the big picture, what is the current best practice for registering users and requiring them to login to use your single page app?</p>
  
  <p>Once a user is logged in, how are the api requests authenticated? Can I store a session but how do I detect for this session in the API calls or is there a token I have to pass in every single API call? Any answers to this would be much appreciated!</p>