class

A programming language concept that allows data and methods to be grouped together. The class concept is fundamental to the notion of an object-oriented programming language. The methods of a class define the set of permitted operations on the class's data (its attributes). This close tie between data and operations means that an instance of a class - an object - is responsible for responding to messages received via its defining class's methods.

In the Java programming language, a type that defines the implementation of a particular kind of object. A class definition defines instance and class variables and methods, as well as specifying the interfaces the class implements and the immediate superclass of the class. If the superclass is not explicitly specified, the superclass will implicitly be Object.

Article I, section 3 of the Constitution requires the Senate to be divided into three classes for purposes of elections. Senators are elected to six-year terms, and every two years the members of one class—approximately one-third of the Senators—face election or reelection. Terms for Senators in Class I expire in 2013, Class II in 2009, and Class III in 2011.

A class, in general, is a representation of a concept. It is an abstract representation of some specific classification of things (hence the name class). The name used to identify a class is the perceptual symbol or word used to denote a concept. In an ontology, a class is more specifically a formal definition of a type of information object that may possess a given set of attributes or properties and specific types of relations to other things. The ontology class is the template for an instance or individual of that type. In other words, the class is the schema or model for information of a given type while an instance of the class is considered to be the actual data.

A user-defined "type", implemented in Perl via a "package" that provides (either directly or by inheritance) methods (that is, subroutines) to handle instances of the class (its objects). See also "inheritance".

Acronym for custom local area signaling service.