Agile

The Agile Manifesto, published in 2001, formalized a set of values that had been emerging across the software industry: individuals and interactions over processes, working software over documentation, customer collaboration over contracts, and responding to change over following a plan. These four value statements, backed by twelve principles, shifted the dominant paradigm from plan-driven waterfall models to iterative, feedback-rich delivery.

In practice, agile teams work in short iterations — typically one to four weeks — producing a potentially shippable increment at the end of each cycle. Requirements are captured as a prioritized backlog rather than a fixed specification, allowing scope to evolve as stakeholders learn from each release. Cross-functional teams own delivery end-to-end, reducing handoffs and accelerating feedback loops between development, testing, and operations.

Agile itself is an umbrella term. Concrete implementations include Scrum, Kanban, Extreme Programming (XP), and SAFe. Most teams adopt a hybrid, selecting practices that fit their context — daily stand-ups from Scrum, WIP limits from Kanban, pair programming from XP — rather than following a single framework prescriptively.