Agile is not a single methodology — it's a mindset and a set of values for managing work in environments where requirements evolve and rapid feedback is essential. Scrum is the most widely adopted framework that implements Agile principles in practice.
The Agile Manifesto
In 2001, seventeen software practitioners met in Snowbird, Utah and published the Agile Manifesto. It defines four core values:
The manifesto doesn't reject the items on the right — it simply values the items on the left more. This nuance is often overlooked.
The 12 Agile Principles (Summarized)
- Deliver working product early and continuously
- Welcome changing requirements, even late in the process
- Deliver frequently — weeks rather than months
- Business and developers must work together daily
- Build projects around motivated individuals; trust them
- Face-to-face conversation is the most effective communication
- Working product is the primary measure of progress
- Maintain a sustainable pace — avoid burnout
- Continuous attention to technical excellence
- Simplicity — maximize the amount of work not done
- Self-organizing teams produce the best results
- Reflect and adjust at regular intervals
What is Scrum?
Scrum is a lightweight framework for developing and sustaining complex products. It is built on empiricism — the idea that knowledge comes from experience and making decisions based on what is observed. Scrum employs an iterative, incremental approach to optimize predictability and control risk.
The Sprint Cycle
Work in Scrum is organized into time-boxed iterations called Sprints, typically lasting 1–4 weeks. Each Sprint follows a predictable rhythm:
Scrum Roles
| Role | Responsibility |
|---|---|
| Product Owner | Owns the Product Backlog. Defines priorities, represents stakeholders, and ensures the team builds the most valuable thing first. One person, not a committee. |
| Scrum Master | Serves the team by removing impediments, facilitating Scrum events, and coaching the team on Agile practices. Not a traditional manager — more of a servant-leader. |
| Development Team | Cross-functional group (typically 3–9 people) that does the actual work. Self-organizing — they decide how to accomplish the Sprint Goal. No sub-teams or titles within. |
Scrum Artifacts
- Product Backlog: An ordered list of everything that might be needed in the product. Continuously refined and re-prioritized by the Product Owner.
- Sprint Backlog: The subset of Product Backlog items selected for the current Sprint, plus a plan for delivering them.
- Increment: The sum of all completed Product Backlog items at the end of a Sprint. It must meet the Definition of Done — an agreed-upon standard of quality.
Agile vs. Waterfall
| Aspect | Waterfall | Agile / Scrum |
|---|---|---|
| Approach | Linear, sequential | Iterative, incremental |
| Requirements | Fixed upfront | Evolve over time |
| Delivery | One big release at the end | Working increment every Sprint |
| Change | Resisted, costly | Welcomed, expected |
| Customer Involvement | Beginning and end | Continuous throughout |
| Risk | Discovered late | Identified early via short cycles |