Fundamentals of Software Architecture, 2nd Edition

Chapter 2. Modularity

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Architects and developers have struggled with the concept of modularity for quite some time, as is evident from the following quote:

95% of the words [written about software architecture] are spent extolling the benefits of “modularity” and little, if anything, is said about how to achieve it.

Glenford J. Myers, _Composite/Structured Design_ (Van Nostrand Reinhold

Different platforms offer different reuse mechanisms for code, but all support some way of grouping related code together into modules. While this concept is universal in software architecture, it has proven slippery to define. A casual internet search yields dozens of definitions, with no consistency (and some contradictions). As mentioned earlier, this isn’t a new problem. However, because no recognized definition exists, we must jump into the fray and provide our own definitions for the sake of consistency throughout the book.

Understanding modularity ...