What is an agile or agile methodology?

The agile methodology was created by the Agile Alliance in 2001 and has since been adopted by many software development companies. It uses a human-centered approach to planning, organizing and developing software. An application of the Agile methodology will produce products that are delivered quickly instead of in stages as with old, waterfall-style software development. It also permits for flexible teams, frequent changes to the requirements of a product during its lifecycle and continuous feedback from customers or clients on each new iteration of a product.

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