What is MVC?
Most programmers know this, but interviewers will likely look for a deep understanding of MVC, and some explanation or examples on how/why/ when you used it.
MVC - Model, View, Controller - is simply a way of organizing your code into 3 separate layers each with there own job.
Model - Usually contains data access code and all of you business logic code.
View - Contains markup/design code, generally html,xml, json.
Controller - Usually contains very little code, just whatever is needed to call the Model code and render the View code.