OAuth2.0 is an open authorization protocol, which allows accessing the resources of the resource owner by enabling the client applications on HTTP services such as Facebook, GitHub, etc. It allows sharing of resources stored on one site to another site without using their credentials. It uses username and password tokens instead.
This tutorial is designed for software programmers who would like to understand the concepts of OAuth. This tutorial will give you enough understanding on OAuth from where you can take yourself to higher levels of expertise.
Before proceeding with this tutorial, you should have a basic understanding of authorization and authentication of a basic client server application model.