Data are individual elements that, when strung together, represent a piece of information. This statement applies to digital data. In contrast, analog data consists of a continuous string of individual elements that could represent a physical quantity and its changes. Thereby the single values and their size can reflect the amplitude and the time course of an analog function. The analog way of viewing accommodates the human way of thinking.
Digital data is determined by the length of the data word and by the conversion of the binary units(bits) into alphanumeric characters, into letters, digits and symbols. Digital data cannot be picked up by human senses, but are processed in data processing equipment, in computers, processors, central processing units, etc., and stored in storage systems.
Digital data can be arranged in a structure, then one speaks of structured data, otherwise of unstructured data or semistructured data. In addition to the aforementioned forms, there is also synthetic data. Structured data is based on an ordering system, which means that the data is arranged systematically. Terms and values can be assigned to them. In contrast to structured data, unstructured data is not subject to an ordering system. The data sets are not indexed and cannot be searched for terms. Semistructured data is also not subject to a structural principle. In contrast to unstructured data, however, they contain structural information.
According to DIN 44300, a standard dealing with information processing, data and data structures are also dealt with. According to this definition, data are defined as characters or continuous functions that serve the purpose of processing on the basis of known or assumed arrangements.