Editing Waterfall model (section)

==History==
The first known presentation describing the use of such phases in software engineering was held by [[Herbert D. Benington]] at the Symposium on Advanced Programming Methods for Digital Computers on 29 June 1956.<ref>{{Citation |publisher=Office of Naval Research, Dept. of the Navy |location=[Washington, D.C.] |title=Symposium on advanced programming methods for digital computers |author=United States, Navy Mathematical Computing Advisory Panel |date=29 June 1956 |oclc=10794738 }}</ref>
This presentation was about the development of software for [[Semi Automatic Ground Environment|SAGE]]. In 1983, Benington republished his paper with a foreword explaining that the phases were on purpose organized according to the specialization of tasks, and pointing out that the process was not in fact performed in a strict top-down fashion, but depended on a prototype.<ref name="benington">{{cite journal |last=Benington |first=Herbert D. |title=Production of Large Computer Programs |journal=IEEE Annals of the History of Computing |date=1 October 1983 |volume=5 |issue=4 |pages=350–361 |doi=10.1109/MAHC.1983.10102 |publisher=IEEE Educational Activities Department |s2cid=8632276 |url=http://sunset.usc.edu/csse/TECHRPTS/1983/usccse83-501/usccse83-501.pdf |access-date=2011-03-21}} {{webarchive |url=https://web.archive.org/web/20110718084251/http://sunset.usc.edu/csse/TECHRPTS/1983/usccse83-501/usccse83-501.pdf |date=July 18, 2011 }}</ref>
{{better source needed|date=March 2021|reason=the referenced article neither uses the term waterfall nor describes that there was only one recognized way of developing software}}

Although the term "waterfall" is not used in the paper, the first formal detailed diagram of the process later known as the "waterfall model" is often<ref>{{cite journal |last1=Larman |first1=Craig |last2=Basili |first2=Victor |title=Iterative and Incremental Development: A Brief History |journal=Computer |date=June 2003 |volume=36 |issue=6 |pages=47–56 |doi=10.1109/MC.2003.1204375 |url=https://www.craiglarman.com/wiki/downloads/misc/history-of-iterative-larman-and-basili-ieee-computer.pdf}}</ref> cited as coming from a 1970 article by [[Winston W. Royce]].<ref name="royce">{{Citation |surname=Royce |given=Winston |title=Managing the Development of Large Software Systems |journal=Proceedings of IEEE WESCON |volume=26 |issue=August | year=1970 | pages=1–9 |url=https://www-scf.usc.edu/~csci201/lectures/Lecture11/royce1970.pdf }}</ref><ref>{{ cite web | url=http://www.informatik.uni-bremen.de/uniform/vm97/def/def_w/WATERFALL.htm | title=Waterfall | website=Bremen University - Mathematics and Computer Science }}</ref><ref>{{Cite book|last1=Abbas|first1=Noura|last2=Gravell|first2=Andrew M.|last3=Wills|first3=Gary B.|title=Agile Processes in Software Engineering and Extreme Programming |chapter=Historical Roots of Agile Methods: Where Did "Agile Thinking" Come From? |date=2008|editor-last=Abrahamsson|editor-first=Pekka|editor2-last=Baskerville|editor2-first=Richard|editor3-last=Conboy|editor3-first=Kieran|editor4-last=Fitzgerald|editor4-first=Brian|editor5-last=Morgan|editor5-first=Lorraine|editor6-last=Wang|editor6-first=Xiaofeng|chapter-url=https://eprints.soton.ac.uk/266606/1/xp2008camera_ready.pdf|series=Lecture Notes in Business Information Processing|volume=9 |language=en|location=Berlin, Heidelberg|publisher=[[Springer Science+Business Media |Springer]] |pages=94–103|doi=10.1007/978-3-540-68255-4_10|isbn=978-3-540-68255-4}}</ref> However, he commented that it had major flaws stemming from how testing only happened at the end of the process, which he described as being "risky and [inviting] failure".<ref name="royce" /> The rest of his paper introduced five steps which he felt were necessary to "eliminate most of the development risks" associated with the unaltered waterfall approach.<ref name="royce" />

Royce's five additional steps (which included writing complete documentation at various stages of development) never took mainstream hold, but his diagram of what he considered a flawed process became the starting point when describing a "waterfall" approach.<ref>Conrad Weisert, [http://www.idinews.com/waterfall.html Waterfall methodology: there's no such thing!]</ref><ref name=":inheriting_agile">{{cite book |last1=Lineberger |first1=Rob |title=Inheriting Agile: The IT Practitioner's Guide to Managing Software Development in a Post-Agile World |date=Apr 25, 2024 |publisher=Sandprint Press |location=Durham, NC |isbn=9798989149605 |page=36 |url=https://books.google.com/books?id=kTit0AEACAAJ}}</ref>

The earliest use of the term "waterfall" may have been in a 1976 paper by Bell and Thayer.<ref>Bell, Thomas E., and T. A. Thayer.[http://pdf.aminer.org/000/361/405/software_requirements_are_they_really_a_problem.pdf Software requirements: Are they really a problem?] ''Proceedings of the 2nd international conference on Software engineering.'' IEEE Computer Society Press, 1976.</ref>{{better source needed|date=March 2021|reason=may have been? The use of a term in a paper doesn't mean it was the first use of the term.}}

In 1985, the [[United States Department of Defense]] adopted the waterfall model in the [[DOD-STD-2167]] standard for working with software development contractors. This standard referred for iterations of a software development<ref name=":1">{{Cite book |title=DOD-STD-2167 - Military Standard : Defence System Software Development" |date=1985-06-04 |publisher=Department of Defence, United States of America |pages=11}}</ref> to "''the sequential phases of a software development cycle''" and stated that "''the contractor shall implement a software development cycle that includes the following six phases: Software Requirement Analysis, Preliminary Design, Detailed Design, Coding and Unit Testing, Integration, and Testing''".<ref name=":1" /><ref>{{Cite web|url=http://www.product-lifecycle-management.com/download/DOD-STD-2167A.pdf|title=Military Standard Defense System Software Development}}</ref>