Model: The model is, in effect, the application’s business layer. It usually consists of objects that represent the business entities that make up the application, such as customers and products.
View: The view is the application’s user interface. In a Web application, this consists of one or more HTML pages that define the look and feel of the application.
Controller: The controller manages the events processed by the application. The events are usually generated by user-interface actions, such as the user clicking a button or selecting an item from a drop-down list.