title: Working of an N-tier application
body: <p>How does an N-tier application works if some layer is written in one language and other layer is written in another language? How does a compiler works in such a situation? Can I use qt C++ to make gui with logic layer written in C#?</p>
  
  <p>Edit: Suppose a desktop application is to be built with mvc pattern. I was thinking that if its gui(the view) is written in qt then what programming language could be used to make the controller? What language can 'accelerate' processing of inputs from ui? </p>