Real-time data processing is the execution of data in a short time period, providing near-instantaneous output.

The processing is done as the data is inputted, so it needs a continuous stream of input data in order to provide a continuous output. Good examples of real-time data processing systems are bank ATMs, traffic control systems and modern computer systems such as the PC and mobile devices. In contrast, a batch data processing system collects data and then processes all the data in bulk in a later time, which also means output is received at a later time.
A real-time data processing system is able to take input of rapidly changing data and then provide output near instantaneously so that change over time is readily seen in such a system.