These systems incorporate expertise in order to aid managers in diagnosing problems or in problem-solving . The components of accounting systems such as payroll, general ledger are, it should be obvious, usually batch processing systems, and also transaction processing systems that are transformational systems. Systems for determination of sample sizes for audit testing, on the other hand may be decision support systems. Specification of any system before its development is crucial. Specifications perform for information systems the same function that blue-prints and engineering specifications perform for physical structures.
Specifications serve as benchmarks for evaluating designs as well as their implementation.
In the development of information systems in business, informal specifications through graphical modeling have been used at least since late 70s. We shall be studying many of these modeling tools. While their use in business systems development is in its very early stages, they are expected to play an important role in the future. These formal specification techniques attempt to mathematically specify structure, function, and behavior of information systems. How it responds to events and stimuli.