I am trying to understand Rails a little deeper through the lenses of object oriented programming.

When building a basic app, the property and methods of a model seems more apparent and visual as the developer defines properties and methods like find and all are used often. 

But I am not sure what property and method a controller has and what is used and when it is used.

I've thought of using the .method method to see what method the Application Controller has but I couldn't figure out what to type in the console for the object slot.

Bottomline is that I know what a controller is doing in theory but when it comes to actual source code, not sure which part of the code represents an ApplicationController.

What kind of methods and properties are used for say a simple CRUD application like a blog?