A term used predominantly in the context of industrial, business, governmental, and other organizations: within that context it refers (a) to a class of computer applications, (b) to a function within the organization.
While it is hard to generalize, data-processing applications may be characterized as those that store and process large quantities of data on a routine basis, in order to be able to produce (regularly or on request) information that is predictably needed by an organization's employees, by its customers or suppliers, by government, or by any other organization. They are often referred to broadly as commercial applications. Typical applications within this category include financial accounting, cost and management accounting, market research and sales forecasting, order processing, investment analysis, financial modeling, stock control, production planning and control, transport planning and control, payroll, and personnel records. Cobol, since its introduction in 1960, has been the most commonly used language for data processing, though it has progressively been usurped by more modern high-level languages and by fourth-generation languages. Data-processing systems are normally long-lived (apart from the need to redesign/rewrite them periodically, they may well last as long as the host organization), and they handle data that is large in volume and complex in structure (which leads to a major concern for the problems and costs of data input and storage).
The data-processing function within an organization is that department responsible for the development and operation of application systems (largely of the types listed above) on behalf of other parts of the organization. Its tasks normally include systems analysis and design, program development and maintenance, database administration, computer operation, data preparation, data control, and network management. The data-processing department may not, however, be responsible for all data-processing applications within an organization, especially in the face of the widespread use of individual desktop computers, and conversely it may have responsibility for some applications that are not usually thought of as data processing (e.g. industrial process control).
In recognition that a lot of clerical and unit-record tasks could be described as data processing, the terms automatic data processing (ADP) or electronic data processing (EDP) were used in the 1960s, and can still occasionally be encountered. The term integrated data processing (IDP) also had some limited use as it became clear that much of an organization's data was common to separately developed systems, and the effort was made to integrate or rationalize them; that effort has mainly been diverted into the growth of databases and database management systems.
The term data processing is used in contexts other than the one described above: for instance, scientific data processing means the fairly straightfoward processing of large quantities of experimental results, and personal data processing means an individual's use of a microcomputer to keep personal records.