Agile
Agile is an approach to software and product development that delivers work in small, frequent increments and uses feedback from customers and the team to adjust direction along the way. Its values and principles were set out in the Manifesto for Agile Software Development in 2001, and frameworks such as Scrum and Kanban are common ways to put them into practice.
How Agile Works
Agile is a set of values and principles rather than a single method. In 2001, seventeen software practitioners signed the Agile Manifesto, which states four values:
- Individuals and interactions over processes and tools.
- Working software over comprehensive documentation.
- Customer collaboration over contract negotiation.
- Responding to change over following a plan.
The manifesto adds that while there is value in the items on the right, the items on the left are valued more. Twelve supporting principles turn these values into working guidance, including delivering working software frequently, "from a couple of weeks to a couple of months, with a preference to the shorter timescale," welcoming changing requirements even late in development, and treating working software as the primary measure of progress.
In practice, agile teams share a few habits:
- Short cycles: work is planned and delivered in small slices, such as two-week sprints or a continuous flow.
- A prioritized backlog: a single ordered list of work, the product backlog, replaces a fixed upfront specification.
- Frequent feedback: working increments are shown to users and stakeholders so the team can change course.
- Self-organizing, cross-functional teams: the people doing the work decide how to do it.
- Regular reflection: the team reviews and improves its own way of working, often in a retrospective.
Several frameworks apply these ideas in different ways. Scrum organizes work into fixed-length sprints with defined accountabilities. Kanban manages a continuous flow of work with limits on work in progress. Extreme Programming (XP) focuses on engineering practices such as test-driven development, pair programming and continuous integration. Lean software development, adapted from lean manufacturing, concentrates on removing waste and shortening the time from idea to delivered value.
Why Agile Matters
Traditional plan-driven development, often called waterfall, assumes requirements can be known in advance and delivers the product at the end of a long project. When needs change or early assumptions prove wrong, problems surface late, when they are expensive to fix. Agile reduces this risk by putting working software in front of people early and often, so the team learns while it can still change course cheaply.
For product managers, agile shifts the job from writing a complete specification upfront to continuously deciding what is most valuable to build next, based on evidence. It does not remove the need for planning or documentation; it keeps them lighter and revises them as the team learns.
Agile is also easy to adopt in name only. Teams can hold daily stand-ups and two-week sprints while scope is fixed months in advance and customer feedback never changes the plan. That is agile ceremony without agile behavior. The test is whether what the team learns actually changes what it builds next.
Agile on its own focuses on delivering software well. It says less about whether the team is building the right thing, which is why many product teams pair it with explicit discovery work, as in dual-track agile. Solo founders can apply the same principles with very little process: lightweight agile for solo founders covers prioritizing, limiting work in progress and shipping smaller slices.
Agile Example
A team is building a scheduling feature for a clinic management app. Instead of specifying every screen for a six-month project, they release a basic booking flow to one clinic after three weeks. Receptionists report that most bookings happen by phone, so the team prioritizes a fast staff-side booking screen over the patient portal they had planned. Each later increment is shaped by what they learn, and the patient portal ships later in a simpler form.
Agile vs. Scrum
Agile is the broader philosophy: the values and principles of the manifesto. Scrum is one specific framework for applying them, with defined accountabilities, events and artifacts. A team can be agile without Scrum, for example by using Kanban, and a team can run Scrum's events mechanically while ignoring agile values.