In 1988, an article in The Journal of Object Technology (JOT) by two ex-PARC employees presented MVC as a general "programming paradigm and methodology" for Smalltalk-80 developers. The Smalltalk-80 environment also includes an "MVC Inspector," a development tool for viewing the structure of a given model, view, and controller side-by-side.
A View is also coupled to a model object, but the structure of that object is left up to the application programmer. In this scheme, a View represents some way of displaying information to the user, and a Controller represents some way for the user to interact with a View. It provides abstract View and Controller classes as well as various concrete subclasses of each that represent different generic widgets. Smalltalk-80 supports a version of MVC that evolved from this one. This design also includes an Editor as a specialized kind of Controller used to modify a particular View, and which is created through that View. A Controller is an organizational part of the user interface that lays out and coordinates multiple Views on the screen, and which receives user input and sends the appropriate messages to its underlying Views. A View is a visual representation of a Model, retrieving data from the Model to display to the user and passing requests back and forth between the user and the Model. In their final design, a Model represents some part of the program purely and intuitively. After discussing it with the other Smalltalk developers, he and the rest of the group settled on Model, View, and Controller instead. His design initially had four parts: Model, View, Thing, and Editor. : 330 He wanted a pattern that could be used to structure any program where users interact with a large, convoluted data set. Trygve Reenskaug created MVC while working on Smalltalk-79 as a visiting scientist at the Xerox Palo Alto Research Center (PARC) in the late 1970s. One of the seminal insights in the early development of graphical user interfaces, MVC became one of the first approaches to describe and implement software constructs in terms of their responsibilities. Popular programming languages have MVC frameworks that facilitate the implementation of the pattern. Traditionally used for desktop graphical user interfaces (GUIs), this pattern became popular for designing web applications. This is done to separate internal representations of information from the ways information is presented to and accepted from the user. Model–view–controller ( MVC) is a software architectural pattern commonly used for developing user interfaces that divide the related program logic into three interconnected elements. Diagram of interactions within one possible take on the MVC pattern
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