Editing Systems development life cycle (section)

== Overview ==
A systems development life cycle is composed of distinct work phases that are used by systems engineers and systems developers to deliver [[information system]]s. Like anything that is manufactured on an assembly line, an SDLC aims to produce high-quality systems that meet or exceed expectations, based on requirements, by delivering systems within scheduled time frames and cost estimates.<ref>{{cite web|url=http://foldoc.org/Systems+Development+Life+Cycle |title=Systems Development Life Cycle from |publisher=FOLDOC |access-date=2013-06-14}}</ref> Computer systems are complex and often link components with varying origins. Various SDLC methodologies have been created, such as [[Waterfall model|waterfall]], [[Spiral model|spiral]], [[Agile software development|agile]], [[Software prototyping#Throwaway prototyping|rapid prototyping]], [[Incremental development|incremental]], and synchronize and stabilize.<ref>{{cite web |url=http://condor.depaul.edu/~jpetlick/extra/394/Session2.ppt |title=Software Development Life Cycle (SDLC)}}</ref>

SDLC methodologies fit within a flexibility spectrum ranging from agile to iterative to sequential. Agile methodologies, such as [[Extreme Programming|XP]] and [[Scrum (development)|Scrum]], focus on lightweight processes that allow for rapid changes.<ref>{{Cite web | url=https://aristeksystems.com/blog/sdlc-overview/| title=SDLC Overview: Models & Methodologies| access-date=2021-12-12}}</ref> [[Iterative and incremental development|Iterative]] methodologies, such as [[Rational Unified Process]] and [[dynamic systems development method]], focus on stabilizing project scope and iteratively expanding or improving products. Sequential or big-design-up-front (BDUF) models, such as waterfall, focus on complete and correct planning to guide larger projects and limit risks to successful and predictable results.<ref>{{Cite book |last=Arden |first=Trevor |title=Information technology applications |date=1991 |publisher=Pitman |isbn=978-0-273-03470-4 |location=London}}</ref> [[Anamorphic development]] is guided by project scope and adaptive iterations.

In [[project management]] a project can include both a [[project life cycle]] (PLC) and an SDLC, during which somewhat different activities occur. According to Taylor (2004), "the project life cycle encompasses all the activities of the [[project]], while the systems development life cycle focuses on realizing the product [[requirement]]s".<ref>{{cite book |first=James |last=Taylor |year=2004 |title=Managing Information Technology Projects |page=39}}</ref>

SDLC is not a methodology per se, but rather a description of the phases that a methodology should address. The list of phases is not definitive, but typically includes planning, analysis, design, build, test, implement, and maintenance/support. In the Scrum framework,<ref>{{cite web |url=https://www.scrum.org/resources/what-is-scrum |title=What is Scrum? |date=December 24, 2019 }}</ref> for example, one could say a single user story goes through all the phases of the SDLC within a two-week sprint. By contrast the waterfall methodology, where every business requirement{{Citation needed|date=August 2021}} is translated into feature/functional descriptions which are then all implemented typically over a period of months or longer.{{Citation needed|date=August 2021}}