Agile

Agile is a family of software development approaches built on the idea that teams should deliver working software early and often, then adjust based on what they learn. The term comes from the Manifesto for Agile Software Development, written in 2001 by 17 practitioners who wanted a lighter alternative to heavy, document-driven processes. It is a set of values and principles rather than a single method, so teams apply it through frameworks such as Scrum, Kanban, and Extreme Programming (XP).

In practice, an Agile team breaks a large goal into small pieces of work, such as user stories, and completes a few of them in each short cycle, often one to four weeks long. At the end of each cycle the team shows the result to users or stakeholders (the people with an interest in the product), gathers feedback, and reprioritizes what comes next. Regular reflection meetings, called retrospectives, let the team improve its own way of working as well as the product.

A useful analogy is driving with a GPS instead of a printed map. A printed map fixes the whole route before you leave, while a GPS checks your position constantly and reroutes when a road is closed. Agile works the same way: the plan is expected to change as the team learns more about its users, the technology, and the market.

Agile is often confused with Scrum, but Scrum is just one specific framework that follows Agile values; Kanban is another. It is also commonly contrasted with the Waterfall model, in which requirements, design, building, and testing happen in long sequential phases and working software appears only near the end. Agile does not mean having no plan or no documentation; it means planning in smaller steps and writing documentation that is actually useful.