Issues with Relationships

You can take a look at the app I'm referring to at:

So, I've built this question & answer app... kind of. I can get the answers to be listed on their respective questions but I cannot figure out how to get the user info to be displayed on those questions/answers. For example I'd like to put the username next to each answer and the username next to each question. Also, when viewing the show action of the users controller, I'd like to be able to see a list of that particular user's questions and answers.

There are three tables: questions, answers and users. Can you take a look at the github repository and try to point me in the right direction for what steps I should take/concepts I should learn in order to achieve what I'm trying to do?

I may be wrong but I think you may find it difficult to get someone to go to the trouble of looking at your whole app in order to understand your problem. For me, at least, you would be better to provide the model relationships (has_many, belongs_to etc) and try and reduce your problem to it's simplest level. The less extraneous detail the better. So for example exactly where you want to show the username is not relevant to the question, I think what you want to ask is 'if I have an answer how do I determine the username for that answer?' That depends only on the model relationships. It is even possible that in the act of trying to refine exactly what question you are trying to ask you might well realise that you know the answer already.

Have you read the Rails Guides on ActiveRecord Associations? That may well help.