Editing Structure (section)

== Software ==
{{Main|Software architecture}}

Software architecture is the specific choices made between possible alternatives within a framework. For example, a framework might require a database and the architecture would specify the type and manufacturer of the database. The [[Structure chart|structure]] of software is the way in which it is partitioned into interrelated components. A key structural issue is minimizing dependencies between these components. This makes it possible to change one component without requiring changes in others.<ref>{{cite book|last1=Gorton|first1=Ian|title=Essential software architecture|date=2011|publisher=Springer|location=Berlin|isbn=9783642191763|edition=2nd}}</ref>{{rp|3}} The purpose of structure is to [[Program optimization|optimise]] for (brevity, readability, traceability, isolation and encapsulation, maintainability, extensibility, performance and efficiency), examples being: [[Computer language|language choice]], [[Indentation style|code]], [[API|functions]], [[Class browser|libraries]], [[makefile|builds]], [[Package manager|system evolution]], or diagrams for [[Control structure diagram|flow logic]] and [[Nassi–Shneiderman diagram|design]].<ref>{{cite book|last1=Diehl|first1=Stephan|title=Software visualization : visualizing the structure, behaviour, and evolution of software ; with 5 tables|url=https://archive.org/details/softwarevisualiz00dieh_179|url-access=limited|date=2007|publisher=Springer|location=Berlin|isbn=978-3540465041|pages=[https://archive.org/details/softwarevisualiz00dieh_179/page/n45 38]–47}}</ref> Structural elements reflect the requirements of the application: for example, if the system requires a high fault tolerance, then a redundant structure is needed so that if a component fails it has backups.<ref>{{cite book|last1=Bernardi|first1=Simona|last2=Merseguer|first2=José|last3=Petriu|first3=Dorina Corina|title=Model-Driven Dependability Assessment of Software Systems|date=2013|publisher=Springer Berlin Heidelberg|location=Berlin, Heidelberg|isbn=9783642395123|pages=46–47}}</ref> A high redundancy is an essential part of the design of several systems in the [[Space Shuttle]].<ref>{{cite web|title=Computers in the Space Shuttle Avionics System|url=https://history.nasa.gov/computers/Ch4-4.html|website=Computers in Spaceflight: The NASA Experience|date=March 1988 |access-date=2 October 2015|archive-date=9 October 2023|archive-url=https://web.archive.org/web/20231009121408/https://history.nasa.gov/computers/Ch4-4.html|url-status=live |last1=Tomayko |first1=James E. }}</ref>