[augustk]

An abstract data type (ADT) is a structured type for which a client cannot access the data components for variables of this type. The client understands the type in terms of its operations, provided by a set of functions which operates on variables of this type. The set of functions is called the interface of the ADT. Note that this definition requires information hiding but not inheritance or polymorphism.

[JonChesterfield]

How would you distinguish that definition from one for "type"?

[augustk]

> How would you distinguish that definition from one for "type"?

The crucial difference between an abstract data type and a concrete data type is that the content is hidden in the former case.