Confused about how OAuth actually works? I was too. Here's a handy graphic for you to visualize the process.
The OAuth Process
And I highly recommend you watch this video by Richard Schneeman.
Whether you're trying to implement an OAuth client, or OAuth Provider, or you just want to know why you keep getting redirected to twitter for authorization it pays to understand OAuth 2 and how the flow works. Tune in to this quick example and understand OAuth a bit better today.
Be confused no more.