Classification by mode of processing

• Batch processing systems: The transactions are collected as they occur, but processed periodically, say, once a day or week.

• On-line batch systems: The transation information is captured by on-line data-entry devices and logged on the system, but it is processed periodically as in batch processing systems.

• On-line Real-time systems: The transaction data capture as well as their processing in order to update records (and generate reports) is carried out in real-time as the transaction is taking place.