MVC Design Pattern

In today's software applications that need to deal with the  presentation of a huge amount of data to the end user, a software developer tries to make the application loosely coupled via separating the data (model) from the user interface (view) concerns. 

To meet the same purpose MVC design patterns were introduced. 

MVC design pattern allows to the user to make the application modules to be loosely coupled thus making the code more flexible when the client requires to add few more functionalities to the existing application.

MVC allows to introduce the changes to the user interface without affecting data handling mechanism. Even it allows the data to get reorganized without demanding for any change to the user interface. 

M in MVC stands for the MODEL
V in MVC stands for the VIEW
C in MVC stands for the CONTROLLER

MODEL

--Model section in an  application allows to use a persistent storage (such as a database) to store and manipulate the data using a programming language. 
--Model in MVC encapsulates the data access layer.
--Model implements all the complex business logics and makes the application more modular and reusable.

VIEW

-- View Section in the MVC pattern renders the data into a more interactive and presentable form.
-- Typically, View Section in the MVC pattern consists of the user interface elements. 
-- Even there may exist the multiple views for a single model to meet the variety of purposes.

CONTROLLER

-- A Controller Section in the MVC pattern manages all the requests coming through the user interfaces.
-- Only the controller is always responsible for accessing the model and rendering various UIs according to the requirements.
-- Controller delegates the various user requests using the configuration files in the XML formats.

Read more at :
www.roseindia.net/struts/mvc-architecture.shtml