As a serious programmer, how do you answer the question What is MVC?

In my mind, MVC is sort of a nebulous topic — and because of that, if your audience is a learner, then you're free to describe it in general terms that are unlikely to be controversial.

However, if you are speaking to a knowledgeable audience, especially an interviewer, I have a hard time thinking of a direction to take that doesn't risk a reaction of "well that's not right!...".  We all have different real-world experience, and I haven't truly met the same MVC implementation pattern twice.

Specifically, there seem to be disagreements regarding strictness, component definition, separation of parts (what piece fits where), etc.

So, how should I explain MVC in a way that is correct, concise, and uncontroversial?

MVC is a software architecture - the structure of the system - that separates domain/application/business (whatever you prefer) logic from the rest of the user interface. It does this by separating the application into three parts: the model, the view, and the controller.

The model manages fundamental behaviors and data of the application. It can respond to requests for information, respond to instructions to change the state of its information, and even to notify observers in event-driven systems when information changes. This could be a database, or any number of data structures or storage systems. In short, it is the data and data-management of the application.

The view effectively provides the user interface element of the application. It'll render data from the model into a form that is suitable for the user interface.

The controller receives user input and makes calls to model objects and the view to perform appropriate actions.

All in all, these three components work together to create the three basic components of MVC.
