Class hierarchy

This article is about the computer science concept. For the sociology concept, please see social class. This article is about the computer science concept. For the sociology concept, please see social class. A class hierarchy or inheritance tree in computer science is a classification of object types, denoting objects as the instantiations of classes (class is like a blueprint, the object is what is built from that blueprint) inter-relating the various classes by relationships such as 'inherits', 'extends', 'is an abstraction of', 'an interface definition'. In object-oriented programming, a class is a template that defines the state and behavior common to objects of a certain kind. A class can be defined in terms of other classes. The concept of class hierarchy in computer science is very similar to taxonomy, the classifications of species. The relationships are specified in the science of object-oriented design and object interface standards defined by popular use, language designers (Java, C++, Smalltalk, Visual Prolog) and standards committees for software design like the Object Management Group.