Agile Manifesto

Agile software development describes a set of principles for software development under which requirements and solutions evolve through the collaborative effort of self-organizing cross-functional teams. It advocates adaptive planning, evolutionary development, early delivery, and continuous improvement, and it encourages rapid and flexible response to change. These principles support the definition and continuing evolution of many software development methods.

The term agile was first coined for this in 2001, in the Manifesto for Agile Software Development (Agile Manifesto), and although originally written as Agile (with a capital A) this is progressively becoming deprecated.

Incremental software development methods can be traced back to 1957. Evolutionary project management and adaptive software development emerged in the early 1970s. During the 1990s, a number of lightweight software development methods evolved in reaction to the prevailing heavyweight methods that critics described as heavily regulated, regimented, and micro-managed. These included: from 1991, rapid application development; from 1994, unified process and dynamic systems development method (DSDM); from 1995, Scrum; from 1996, Crystal Clear and extreme programming (XP); and from 1997, feature-driven development. Although these originated before the publication of the Agile Manifesto in 2001, they are now collectively referred to as agile methods.

In February 2001, 17 software developers met at the Snowbird resort in Utah to discuss lightweight development methods. They published the Manifesto for Agile Software Development, in which they shared that through their combined experience of developing software and helping others to do it they had come to value:

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