Structured Design is a strategy for producing a highly maintainable, easily tested top-down design. The derivative techniques of structured design are transform analysis and transaction analysis. Its evaluative and refinement techniques are coupling, cohesion, and packaging, together with some miscellaneous design heuristics. The documentation tool for structured design is the structured chart. In the structure, the relation and interaction between individual SW modules is given without regard to time or sequence.
Procedure represents both the sequence and conditions under which a process occurs.
During the preliminary design, SW structure is identified without regard for procedure. A consideration of the sequence and conditions of processing inherent within a module is postponed until detailed design. The executive module does not perform any system tasks itself. Some computations or manipulations within the afferent module transform X into Y before delivering Y to its superordinate. Some computations or manipulations within the efferent modules transform X into Y before delivering Y to its subordinate.