Editing History of software engineering (section)

== 1965 to 1985: The software crisis and operating systems ==
Software engineering was spurred by the so-called ''[[software crisis]]'' of the 1960s, 1970s, and 1980s, which identified many of the problems of software development. Many projects ran over budget and schedule. Some projects caused property damage. Through negligence in publishing software with critical bugs, some lost their lives due to software failures. One of the most striking examples of harm through software bugs was the [[Therac-25]] race condition bug. The bug caused a radiation therapy machine to administer overdoses of radiation in cases where low doses should have been used. The software crisis was originally defined in terms of [[productivity]], but evolved to emphasize [[Software quality assurance|quality]]. Some used the term ''software crisis'' to refer to their inability to hire enough qualified programmers.{{citation needed|date=February 2016}} During this time, [[Silicon Valley]] cemented itself as the best location for software engineers to work.<ref>{{Cite journal |last=Saxenian |first=Annalee |date=1983 |title=The Genesis of Silicon Valley |url=https://www.jstor.org/stable/23286110 |journal=Built Environment |volume=9 |issue=1 |pages=7–17 |jstor=23286110 |issn=0263-7960}}</ref> 
* Cost and [[budget overrun|Budget Overruns]]: The [[OS/360]] operating system was a classic example. This decade-long project from the 1960s eventually produced one of the most complex software systems at the time.<ref name="jared2"/> OS/360 was one of the first large (1000 programmers{{Citation needed|date=October 2007}}) software projects. [[Fred Brooks]] claims in ''[[The Mythical Man-Month]]'' that he made a multimillion-dollar mistake of not developing a coherent [[Software architecture|architecture]] before starting development.<ref name="jared2"/>
* Property Damage: Software defects can cause property damage. Poor [[software security]] allows hackers to steal identities, costing time, money, and reputations.{{citation needed|date=February 2016}}
* Life and Death: Software defects can kill. [[Embedded systems]] used in [[radiotherapy]] machines prove the ability to fail so catastrophically that they administered [[lethal dose]]s of [[radiation]] to patients. The most famous of these failures are the ''[[Therac-25]]'' incidents.<ref>{{Cite journal|title = An investigation of the Therac-25 accidents|journal = Computer|date = 1993-07-01|issn = 0018-9162|pages = 18–41|volume = 26|issue = 7|doi = 10.1109/MC.1993.274940|first1 = N.G.|last1 = Leveson|first2 = C.S.|last2 = Turner|citeseerx = 10.1.1.372.412|s2cid = 9691171}}</ref>

[[Peter G. Neumann]] has kept a contemporary list of software problems and disasters.<ref>{{cite journal|url=http://catless.ncl.ac.uk/Risks|title=RISKS-LIST: RISKS-FORUM Digest|journal=The Risks Digest|last1=Neumann |first1=Peter G. }}</ref> The software crisis has been fading from view, because it is psychologically extremely difficult to remain in crisis mode for a protracted period (more than 20 years). Nevertheless, software – especially real-time embedded software – remains risky and is pervasive, and it is crucial not to give in to complacency. Over the last 10–15 years [[Michael A. Jackson (computer scientist)|Michael A. Jackson]] has written extensively about the nature of software engineering, has identified the main source of its difficulties as lack of specialization, and has suggested that his problem frames provide the basis for a "normal practice" of software engineering, a prerequisite if software engineering is to become an engineering science.<ref>Michael Jackson, "Engineering and Software Engineering" in S Nanz ed, The Future of Software Engineering, Springer Verlag 2010; Michael Jackson, Problem Frames: Analyzing and Structuring Software Development Problems; Addison-Wesley, 2001</ref>

One of the largest projects undertaken by software engineers during this time period was the development of modern [[operating system]]s. Starting in Bell Labs and then moving to UC Berkeley, [[Ken Thompson]] and [[Dennis Ritchie]], among other software engineers, worked to create [[Unix V6]] in 1975. Unix V6 was a landmark operating system that set standards for future operating systems and is used today to educate students about proper operating system principles.<ref>{{Cite journal |last1=Kominácká |first1=Jitka |last2=Kominácký |first2=Ladislav |date=2016 |title=Význam hodnoty lokality jako nedílný indikátor kvality života specifického regionu |url=https://doi.org/10.5817/cz.muni.p210-8273-2016-79 |journal=XIX. mezinárodní kolokvium o regionálních vědách. Sborník příspěvků. |location=Brno |publisher=Masaryk university |pages=621–627 |doi=10.5817/cz.muni.p210-8273-2016-79|isbn=978-80-210-8272-4 }}</ref> Moreover, future operating systems built on Unix V6's methods, and its descendants can be grouped into five types of operating system paradigms: Grassroots Systems, Large-Scale Systems, Hybrid Systems, Experimental Systems, and Minor Systems.<ref>{{Cite journal |last=Lauer |first=Hugh C. |date=1981-12-01 |title=Observations on the development of an operating system |url=https://dl.acm.org/doi/abs/10.1145/1067627.806588 |journal=SIGOPS Oper. Syst. Rev. |volume=15 |issue=5 |pages=30–36 |doi=10.1145/1067627.806588 |issn=0163-5980|url-access=subscription }}</ref> In contrast with Unix, software engineers at MIT in 1983 built [[GNU]] (literally "GNU's Not Unix") as an open source alternative to Unix. As an early open source software, GNU was beloved by a small group of developers and its work grew the open source software development community in the 80s.<ref>{{Cite journal |last=Bretthauer |first=David |date=2001-12-26 |title=Open Source Software: A History |url=https://digitalcommons.lib.uconn.edu/libr_pubs/7/ |journal=Published Works}}</ref>