One Billion Knowledgeable

Tony Hoare made several observations on records in 1966, and he particularly put forth the concept of record subclasses, which are record types with shared features that are distinguished by a variant tag and have fields that are exclusive to the variant.

A class is an extendable program-code template used in object-oriented programming that offers starting settings for state (member variables) and behavior implementations (member functions or methods).

As a result, they can more easily simulate dynamic systems (such as the real world, machine learning, and AI).

A class that generates other classes is known as a metaclass in these languages.

Although there is a difference between an interface's definition and implementation, this boundary is often muddled in programming languages because class declarations both define and implement an interface.

Classes can inherit interfaces from the classes they are derived from in languages that support class inheritance.

The operations of any interface of a class must be independent of one another, according to the object-oriented programming paradigm.

Classes can be created by deriving from one or more preexisting classes, creating a hierarchy between the base classes, parent classes, or superclasses and the derived class (also known as a child class or subclass).

Java, for instance, permits a class to implement several interfaces, but it can only derive from a single class.

A superclass is conceptually a superset of all of its subclasses. For instance, in a typical class hierarchy, Square would be a subclass of Rectangle, whereas GraphicObject would be the superclass of Ellipse and Rectangle.