I've gone through the django polls one as well as part of an RoR tutorial, but either those weren't as clear or (more likely) I was too dumb and needed it see it explained several times in different ways, this MEAN stack tutorial made a lot of sense.
On the server side:
- Model (*.model.js) = the database
- Controller (*controller.js) = has all the CRUD calls (create, retrieve, update, delete...)
- View? (*routes.js) = handles the REST calls from the client (web browser) and calls the appropriate functions in controller.js
And the difference between REST and CRUD is explained very well here: