Objects and Types: A Tutorial

Abstract

This paper is a tutorial explaining the concepts that surround abstract data types and object-oriented programming, and the relationships between these groups of concepts. These concepts include types (languagedefied, user-defied, abstract), instantiations, differences between operations and functions, overloading, objects, state, inheritance and, messages. Some of the these trems, e.g. "type", have been well defied. Many others are used in seveml contexts with multiple meanings. This paper is an attempt to identify consistent and meaningful definitions which are the most widely accepted.