ABSTRACT
Some designers simplify the Input-Process-Output (IPO) charts by eliminating the arrows and system flowchart symbols and showing only the text. The Hierarchy plus IPO (HIPO) technique is a tool for planning and/or documenting a computer program. A HIPO model consists of a hierarchy chart that graphically represents the program’s control structure and a set of IPO charts that describe the inputs to, the outputs from, and the functions performed by each module on the hierarchy chart. Using the HIPO technique, designers can evaluate and refine a program’s design, and correct flaws prior to implementation. An IPO chart is prepared to document each of the modules on the hierarchy chart. An overview diagram is a high-level IPO chart that summarizes the inputs to, processes or tasks performed by, and outputs from a module. A detail diagram is a low-level IPO chart that shows how specific input and output data elements or data structures are linked to specific processes.
