In programming languages, an abstract type, unlike Concrete class is a type in a nominative type system which cannot be instantiated. (However, it may have concrete subtypes that do have instances.) An abstract type may have no implementation, or an incomplete implementation. It may include abstract methods or abstract properties that are shared by its subtypes.
A type that is not abstract is called a concrete type.
In many object oriented programming languages, abstract types are known as abstract base classes. In some languages, abstract types with no implementation are known as interfaces. Other names for language features that are (or may be) used to implement abstract types include traits, mixins, flavors, or roles.
Read more about Abstract Type: Signifying Abstract Types, Use of Abstract Types
Famous quotes containing the words abstract and/or type:
““If our minds could get hold of one abstract truth, they would be immortal so far as that truth is concerned. My trouble is to find out how we can get hold of the truth at all.””
—Henry Brooks Adams (1838–1918)
“This type of man who is devoted to the study of wisdom is always most unlucky in everything, and particularly when it comes to procreating children; I imagine this is because Nature wants to ensure that the evils of wisdom shall not spread further throughout mankind.”
—Desiderius Erasmus (c. 1466–1536)