Data processing system
A data processing system is a combination of machines, people, and processes that for a set of inputs produces a defined set of outputs. The inputs and outputs are interpreted as data, facts, information etc. depending on the interpreter's relation to the system.

A term commonly used synonymously with data or storage (codes) processing system is information system. With regard particularly to electronic data processing, the corresponding concept is referred to as electronic data processing system.

A data processing system may involve some combination of:
 Conversion converting data to another form or Language.
 Validation – Ensuring that supplied data is "clean, correct and useful."
 Sorting – "arranging items in some sequence and/or in different sets."
 Summarization – reducing detail data to its main points.
 Aggregation – combining multiple pieces of data.
 Analysis – the "collection, organization, analysis, interpretation and presentation of data.".
 Reporting – list detail or summary data or computed information.

The first machines used for data processing were punched card machines, now computers are used.

Types of data processing systems

By application area

Scientific data processing
Scientific data processing "usually involves a great deal of computation (arithmetic and comparison operations) upon a relatively small amount of input data, resulting in a small volume of output."

Commercial data processing
Commercial data processing "involves a large volume of input data, relatively few computational operations, and a large volume of output."  Accounting programs are the prototypical examples of data processing applications. Information Systems (IS) is the field that studies such organizational computer systems.

Data analysis
"Data analysis is a body of methods that help to describe facts, detect patterns, develop explanations, and test hypotheses."  For example, data analysis might be used to look at sales and customer data to "identify connections between products to allow for cross selling campaigns."

By service type
 Transaction processing systems
 Information storage and retrieval systems
 Command and control systems
 Computing service systems
 Process control systems
 Message switching systems

Examples

Simple example
A very simple example of a data processing system is the process of maintaining a check register.  Transactions— checks and deposits— are recorded as they occur and the transactions are summarized to determine a current balance.  Monthly the data recorded in the register is reconciled with a hopefully identical list of transactions processed by the bank.

A more sophisticated record keeping system might further identify the transactions— for example deposits by source or checks by type, such as charitable contributions.  This information might be used to obtain information like the total of all contributions for the year.

The important thing about this example is that it is a system, in which, all transactions are recorded consistently, and the same method of bank reconciliation is used each time.

Real-world example
This is a flowchart of a data processing system combining manual and computerized processing to handle accounts receivable, billing, and general ledger

See also 
 Scientific computing
 Information processing system (broader term)

References

Further reading 
 Bourque, Linda B.; Clark, Virginia A. (1992) Processing Data: The Survey Example. (Quantitative Applications in the Social Sciences, no. 07-085). Sage Publications. 

Data management
Data processing