Agile Development 101

What is Agile Development?

"Agile Development" is an umbrella term for several iterative and incremental software development methodologies. The most popular agile methodologies include Extreme Programming (XP), Scrum, Crystal, Dynamic Systems Development Method (DSDM), Lean Development, and Feature-Driven Development (FDD).

While each of the agile methods is unique in its specific approach, they all share a common vision and core values (see the Agile Manifesto). They all fundamentally incorporate iteration and the continuous feedback that it provides to successively refine and deliver a software system. They all involve continuous planning, continuous testing, continuous integration, and other forms of continuous evolution of both the project and the software. They are all lightweight, especially compared to traditional waterfall-style processes, and inherently adaptable. What is more important about agile methods is that they all focus on empowering people to collaborate and make decisions together quickly and effectively.

The Evolution of Agile Development

Many of the individual principles and practices that are promoted by agile development have been around for years, even decades. As opposed to implementing these best practices piecemeal, agile methodologies have "packaged" various customer, management, and in some cases, engineering practices and principles together in a way that helps guide teams through the process of rapidly planning and delivering working, tested software. Each of the agile methodologies combines both old and new ideas into refinements that are certainly greater than the sums of their parts.

While it is true that many of the practices associated with agile development have been around for quite some time, the average software development team has yet to embrace many of the principles and practices. Even today, the average software team does not iterate, does not deliver software incrementally, and does not practice continuous planning nor automate testing. Now that these practices have been combined in a manner that can more easily be understood and adopted, the trend appears to be rapidly changing for the better, especially during the last several years.

As with any new way of doing business though, Agile methods have generated quite a bit of controversy within the software community. Yet since their emergence, in project after project, they have continued to deliver higher quality software systems in less time than traditional processes. If you are a software development professional, you definitely owe it to yourself to become familiar with the theory and practice of agile development. Hopefully the information presented on this site can assist you in learning what agile is all about.

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