information hiding concept
Parnas's 1972 idea, made central by Ousterhout: each module should hide one important design decision (the data structure used, the algorithm, the data format).
Parnas's 1972 idea, made central by Ousterhout: each module should hide one important design decision (the data structure used, the algorithm, the data format). Callers don't need to know; if the decision changes, only one module changes. Shallow modules fail at this — they hide nothing. The opposite is information leakage: when one decision shows up in many modules' interfaces and you can't change it without changing them all.