Scrum is a popular agile software development framework, originally written by Ken Schwaber and Jeff Sutherland. It consists of a few simple processes, 3 roles and a variety of artefacts (outputs), which together form a coherent product development process. Scrum is described in The Scrum Guide, which was originally published in 2009.
The Scrum framework is designed for a single product development team. For multiple Scrum teams working on a larger scale, additional approaches and frameworks have been developed, for example Scaled Agile Framework (SAFe).
The Scrum team is composed of 3 roles.
A Scrum team has a single individual performing the Product Owner role which represents the customer. It liaises with business stakeholders and defines the product to be delivered by the project, usually in the form of user stories. It prioritises the user stories (requirements) in the product backlog. The Product Owner is concerned with maximizing the value that the team delivers by bridging the gap between business stakeholders and the technical development team.
The development team consists of a self-organising team of developers. Developers usually means anyone working on the development and support of the system or product, and might include architects, designers, analysts, programmers, testers, and others. Developers perform the work required to meet the goal of delivering increments of value every sprint.
Team members are encouraged to interact directly with business stakeholders to gain maximum understanding and immediacy of feedback. However, all work for the team is authorised by the Product Owner, through prioritised user stories from a sprint backlog.
The Scrum Master role is performed by a single individual and acts as a facilitator by removing any impediments the team faces in delivering the increments. The Scrum Master acts as a barrier between the team and any distracting influences and is therefore not a traditional team leader or project manager but is more of a ‘servant-leader’.
The Scrum Master coaches the team in scrum theory and concepts, facilitates key events and meetings, and encourages the team to grow and improve.
The Scrum Master helps the Product Owner maintain the product backlog and helps the team define the meaning of ‘done’ for the product. It also promotes self-organisation and cross-functionality within the team, helps people and adopt empirical and lean thinking.
A Scrum sprint (iteration or timebox) is a fixed time period in which development work takes place. The duration is agreed and fixed in advance for each sprint and is normally between one week and one month.
Every sprint begins with a sprint planning event. A sprint goal is agreed, and a sprint backlog emerges, which contains the prioritised user stories or features to be completed within the sprit.
At the end of the sprint, a sprint review takes place which is an opportunity for the team to demonstrate progress to, and gain feedback from, stakeholders via a working increment of the product. A sprint retrospective also occurs to identify lessons and improvements for the next sprints.
The scrum team holds a sprint planning event at the start of a sprint. This is where it agrees on the sprint goal based on the priorities set by the Product Owner. It selects product backlog items that contribute towards this goal to form a sprint backlog.
Every day at the same time and place during a sprint, the developers (team members) hold a daily scrum (sometimes called a daily stand up). It lasts 15 minutes. It focuses on inspecting progress towards the sprint goal and identifying any impediments to progress. It does not feature detailed discussions which should occur after the meeting.
This occurs at the end of every sprint and is where the team presents a working increment of the product to stakeholders to elicit their feedback.
For Product Owners this event is an opportunity to review and refine the product backlog with stakeholders.
The sprint retrospective is where the team reflects on the past sprint and identifies and agrees on any actions for process improvement on later sprints.
