Breaking into Subsystems

Decomposition is a significant technique for coping with complexity based on idea of divide and conquers. In dividing a problem into sub problems, the problem becomes less complex and easier to overlook and to deal with. Frequently dividing a problem will lead to sub problems which are small enough so that they can be conquered. After all sub problems have been conquered and solutions to that problem have been found, solutions need to be combine in order to obtain the solution of whole problem. The history of computing has seen two forms of decomposition: object-oriented and process-oriented decomposition.