What is the difference between an abstract data type and a data type?

There is no difference

An abstract data type provides an implementation$-$dependent view of the data, while a data type provides an implementation$-$independent view

An abstract data type is a logical description of how we view the data without regard to how it is implemented. A data type is a specific implementation of an abstract data type.

An data type is a logical description of how we view the data without regard to how it is implemented. An abstract data type is a specific implementation of an abstract data type