Computer Language for AeronauticS and Programming



1. The prototype for an object in an object-oriented language; analogous to a derived type in a procedural language. A class may also be considered to be a set of objects which share a common structure and behaviour. The structure of a class is determined by the class variables which represent the state of an object of that class and the behaviour is given by a set of methods associated with the class.

Classes are related in a class hierarchy. One class may be a specialisation (a "subclass") of another (one of its "superclasses") or it may be composed of other classes or it may use other classes in a client-server relationship. A class may be an abstract class or a concrete class.

See also signature.


2. See type class.


3. One of three types of Internet addresses distinguished by their most significant bits.


3. A language developed by the Andrew Project. It was one of the first attempts to add object-oriented features to C.

Last updated: 1995-05-01

Class 5 switch


The lowest designation used in AT&T's hierarchical General Toll Switching Plan, developed in 1929.

Last updated: 2013-09-14

class hierarchy


In object-oriented programming, a set of classes related by inheritance. Each class is a "subclass" of another class - its "superclass". The subclass contains all the features of its superclass, but may add new features or redefine existing features. The features of a class are the set of attributes (or "properties") that an object of that class has and the methods that can be invoked on it.

If each class has a just one superclass, this is called single inheritance. The opposite is multiple inheritance, under which a class may have multiple superclasses. Single inheritance gives the class hierarchy a tree structure whereas multiple inheritance gives a directed graph. Typically there is one class at the top of the hierarchy which is the "object" class, the most general class that is an ancestor of all others and which has no superclass.

In computing, as in genealogy, trees grow downwards, which is why subclasses are considered to be "below" their superclasses.

When invoking a method on an object, the method is first looked for in the object's class, then the superclass of that class, and so on up the hierarchy until it is found. Thus a class need only define those methods which are specific to it and it will inherit all other methods from all its superclasses. An object of the subclass can do everything that an object of the superclass can and possible more.

C++ calls the superclass the "base class" and the subclass the "derived class" (not to be confused with a derived type).

Last updated: 2014-09-06



An adjective used before or after a noun to describe the original version of something, especially if the original is considered to be better.

Examples include "Star Trek Classic" - the original TV series as opposed to the films, ST The Next Generation or any of the other spin-offs and follow-ups; or "PC Classic" - IBM's ISA-bus computers as opposed to the PS/2 series.

Last updated: 1996-10-27



An object-oriented extension to Ada, said to be like Smalltalk. It is implemented as an Ada preprocessor.

Last updated: 1994-12-05

classical logic


Non-intuitionistic logic.

Last updated: 1995-04-13

Classic C


Classless Inter-Domain Routing


(CIDR) /sid*r/ A technique that summarises a block of Internet addresses in a routing table as an address in dotted decimal notation followed by a forward slash and a two-digit decimal number giving the number of leading one bits in the subnet mask. For example, specifies a subnet mask of 11111111.11111111.11111111.00000000 (binary), implying the block of addresses through

CIDR is "classless" because it is not limited to the subnet masks specified by Internet address classes A, B and C.

According to RFC 1519, CIDR was implemented to distribute Internet address space more efficiently and to provide a mechanism for IP route aggregation. This in turn reduces the number of entries in IP routing tables, enabling faster, more efficient routing, e.g. using routing protocols such as OSPF. CIDR is supported by BGP4.

See also RFC 1467, RFC 1518, RFC 1520.

Last updated: 2006-01-26

class library


A library of reusable classes for use with an object-oriented programming system.

Last updated: 1994-12-05

class method


1. A method that operates on a class object (an object of class "class"). A class method is really just an ordinary object method that happens to operate on class objects.

A class method might, for example, return a list of objects representing the methods and attributes of the given class.

2. A static method.

Last updated: 2014-09-06

class object


In object-oriented programming, an object of class "class" that represents a class at run time. The existence of class objects allows introspection - the ability for a program to discover and modify attributes of its own code. (See self-modifying code).

A class object may also be used for "housekeeping" tasks like keeping count of how many objects of the class have been created, though this may also be done by some kind of collection object.

A class method is a method that operates on class objects.

Last updated: 2014-09-06

Class Oriented Ring Associated Language


(CORAL) A language developed by L.G. Roberts at MIT in 1964 for graphical display and systems programming on the TX-2. It used "rings" (circular lists) from Sketchpad.

["Graphical Communication and Control Languages", L.B. Roberts, Information System Sciences: Proc Second Congress, 1965].

[Sammet 1969, p.462].

Last updated: 1994-11-30

Class-Relation Method


A design technique based on the concepts of object-oriented programming and the Entity-Relationship model from the French company Softeam.

Last updated: 1994-12-05

Nearby terms:

ClarifyClarionClarisCLASPclassClass 5 switchclass hierarchy

Try this search on Wikipedia, Wiktionary, Google, OneLook.