This guide is nice as it provides a short introduction into Angular's features.
I would kindly recommend you to read the Conceptual Overview section of the AngularJS Developer Guide (http://docs.angularjs.org/guide/concepts). This covers the heart of the framework and also parts of its philosophy. If you want to understand WHY AngularJS works the way it does not only WHAT it does then this page will really help you. You will also understand why this is a masterpiece of engineering.
I would kindly recommend you to read the Conceptual Overview section of the AngularJS Developer Guide (http://docs.angularjs.org/guide/concepts). This covers the heart of the framework and also parts of its philosophy. If you want to understand WHY AngularJS works the way it does not only WHAT it does then this page will really help you. You will also understand why this is a masterpiece of engineering.