Data

The contribution of this article is a data concept that is essentially based on the two concepts of information and computable functionality. In short, data is viewed as typed information. A data type is defined as a pair of a set of distinguishable characters (an alphabet) and a set of operations (computable functions) that operate on this alphabet as domain. Two different ways of subtyping in the sense of Liskov and Wing are described, one for restriction and one for extension of existing types. They lead to two different partial orders on types. It is argued that the proposed data concept matches the concept of characteristics (Merkmale) of the automation industry.