Q5. When did Model-View-Controller begin and where is it used?

Answer:

Wikipedia (2009) states that
MVC was first described in 1979 by Trygve Reenskaug, then working on Smalltalk at Xerox PARC. The original implementation is described in depth in the influential paper Applications Programming in Smalltalk-80.

There have been several derivatives of MVC; one of the most known (due to its use by Microsoft) is the Model View Presenter pattern which appeared in the early 1990s and was designed to be an evolution of MVC. However Model–View–Controller still remains very widely used.

In November 2002 the W3C voted to make MVC structures part of their XForms architecture for all future web applications. These specifications will now be integrated directly into the XHTML 2.0 specifications. There are now over 20 vendors that support XForms frameworks with MVC integrated into the application stack.

Reference:

1. Wikipedia (2009). "Model-view-controller". Wikipedia The Free Encyclopedia, Retrieved from URL - http://en.wikipedia.org/wiki/Model%E2%80%93view%E2%80%93controller