In sociology, the main grouping of social stratification in industrial societies, based primarily on economic and occupational factors, but also referring to people's style of living or sense of group identity. Within the social sciences, class has been used both as a descriptive category and as the basis of theories about industrial society. Theories of class may see such social divisions either as a source of social stability (Emile Durkheim) or social conflict (Karl Marx). In the US, little acknowledgment is given to the notion of class. If asked, most Americans identify themselves as middle class, although social scientists use measurements of education level, income, and occupation to ascribe social strata.

In mathematics another name for a set.

1. In object-oriented programming, a generalized category that describes a group of more specific items, called objects, that can exist within it. A class is a descriptive tool used in a program to define a set of attributes or a set of services (actions available to other parts of the program) that characterize any member (object) of the class. Program classes are comparable in concept to the categories that people use to organize information about their world, such as animal, vegetable, and mineral, that define the types of entities they include and the ways those entities behave. The definition of classes in object-oriented programming is comparable to the definition of types in languages such as C and Pascal. See also object-oriented programming.
A class is a data structure that may contain data members (constant and fields), function members (methods, properties, indexers, events, operators, instance constructors, static constructors, and destructors), and nested types. Class types support inheritance, a mechanism whereby a derived class can extend and specialize a base class.
2. For hardware, the method for grouping particular types of devices and buses according to the basic ways that they can be installed and managed by the operating system. The hardware tree is organized by device class, and Windows uses class installers to install drivers for all hardware classes.

Classify.