Abstract Data Types

In computer science, Abstract Data Types (ADT) is a programming methodology where one defines not only the data structure to be used but the processes to manipulate the structure.

Same as the progress abstraction, ADT can be directly support by any programming languages. To support the ADT, there needs to be mechanisms for defining data structures, which is the basis and the primary in ADT. Second encapsulation of data structures and their routines to manipulate the structures into one unit. It can be compiled at one time by placing all definitions in one unit.

In programming languages, there are some common types of ADTs such as Associative Array (we called it Dictionary in Python), method ‘append’, list, queue and priority queue, storage, method ‘pop’ and ‘push’ (in python), string and the tree we have recently learned it. The data structure should only be accessible from code encapsulated with it so that the structure is hidden and protected from the outside. Users need only care for the interface but not how to realize. This means that as long as the users follow the interface, the ADT can be implemented by any method and will never affect the users.

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