Editing Critical path method (section)

== History ==
The CPM is a project-modeling technique developed in the late 1950s by Morgan R. Walker of [[DuPont]] and James E. Kelley Jr. of [[Remington Rand]].<ref>{{cite book |doi=10.1145/1460299.1460318 |chapter=Critical-path planning and scheduling |title=Papers presented at the December 1-3, 1959, eastern joint IRE-AIEE-ACM computer conference on - IRE-AIEE-ACM '59 (Eastern) |date=1959 |last1=Kelley |first1=James E. |last2=Walker |first2=Morgan R. |pages=160–173 |isbn=978-1-4503-7868-0 }}</ref> Kelley and Walker related their memories of the development of CPM in 1989.<ref>{{cite journal
  | last1      = Kelley
  | first1     = James
  | last2     = Walker
  | first2    = Morgan
  | title     = The Origins of CPM: A Personal History
  | journal   = The PM Net Work
  | date = 1989
 | volume    = 3
  | issue     = 2
  | pages     = 7–22
  | url       = https://books.google.com/books?id=jS9aAAAAYAAJ
  }}</ref> Kelley attributed the term "critical path" to the developers of the PERT, which was developed at about the same time by [[Booz Allen Hamilton]] and the [[U.S. Navy]].<ref>{{cite book |last1=Newell |first1=Michael W. |last2=Grashina |first2=Marina N. |title=The Project Management Question and Answer Book |date=2004 |publisher=AMACOM, American Management Association |isbn=978-0-8144-7164-7 |page=98 }}</ref> The precursors of what came to be known as critical path were developed and put into practice by DuPont between 1940 and 1943 and contributed to the success of the [[Manhattan Project]].<ref>{{cite book |doi=10.1061/9780784401606 |title=Management of the Hanford Engineer Works in World War II |date=1996 |last1=Thayer |first1=Harry |isbn=978-0-7844-0160-6 |pages=66–67 }}</ref>

Critical path analysis is commonly used with all forms of projects, including construction, aerospace and defense, software development, research projects, product development, engineering, and plant maintenance, among others. Any project with interdependent activities can apply this method of mathematical analysis. CPM was used for the first time in 1966 for the major skyscraper development of constructing the former [[World Trade Center Twin Towers]] in New York City. Although the original CPM program and approach is no longer used,<ref>A Brief History of Scheduling: [http://www.mosaicprojects.com.au/PDF_Papers/P042_History%20of%20Scheduing.pdf mosaic projects.com.au] {{Webarchive|url=https://web.archive.org/web/20150518071346/http://www.mosaicprojects.com.au/PDF_Papers/P042_History%20of%20Scheduing.pdf |date=May 18, 2015 }}</ref> the term is generally applied to any approach used to analyze a project network logic diagram.