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Scrum

Scrum is an iterative, incremental framework for agile software development.

Characteristics

Scrum is a “process Framework which contains sets of practices and predefined roles. The main roles in Scrum are:

1. the “ScrumMaster”, who maintains the processes
2. the “Product Owner”, who represents the stakeholders (icludes more or less the roles of a Product Mgr. Req. Engineer etc.)
3. the “Team”, a cross-functional group of 7 people +- 2 who do the actual analysis, design, implementation, testing, etc.

During each iteration called “sprint”, typically a two to four week period (with the length being decided by the team), the team creates a potentially shippable product increment (for example, working and tested software). The set of features that go into a sprint come from the product “backlog,” which is a prioritized set of high level requirements of work to be done. Which backlog items go into the sprint is determined during the sprint planning meeting. During this meeting, the Product Owner informs the team of the items in the product backlog that he or she wants completed. The team then determines how much of this they can commit to complete during the next sprint. During a sprint, no one is allowed to change the sprint backlog, which means that the requirements are frozen for that sprint. After a sprint is completed, the team demonstrates the use of the software.

Scrum enables the creation of self-organizing teams by encouraging co-location of all team members, and verbal communication across all team members and disciplines that are involved in the project.

A key principle of Scrum is its recognition that during a project the customers can change their minds about what they want and need (often called requirements churn), and that unpredicted challenges cannot be easily addressed in a traditional predictive or planned manner. As such, Scrum adopts an empirical approach—accepting that the problem cannot be fully understood or defined, focusing instead on maximizing the team’s ability to deliver quickly and respond to emerging requirements.

There are several implementations of systems for managing the Scrum process, which range from yellow stickers and whiteboards, to software packages. One of Scrum’s biggest advantages is that it is very easy to learn and requires little effort to start using.

Ceremonies/Meetings

Daily Scrum
Each day during the sprint, a project status meeting occurs. This is called a “daily scrum”, or “the daily standup”. This meeting has specific guidelines:

* The meeting starts precisely on time.
* All are welcome, but only “pigs” may speak
* The meeting is timeboxed to 15 minutes
* The meeting should happen at the same location and same time every day

During the meeting, each team member answers three questions:

* What have you done since yesterday?
* What are you planning to do today?
* Do you have any problems preventing you from accomplishing your goal? (It is the role of the ScrumMaster to facilitate resolution of these impediments. Typically this should occur outside the context of the Daily Scrum so that it may stay under 15 minutes.)

Scrum of scrums
Each day normally after the daily scrum.

* These meetings allow clusters of teams to discuss their work, focusing especially on areas of overlap and integration.
* A designated person from each team attends.

The agenda will be the same as the Daily Scrum, plus the following four questions:

* What has your team done since we last met?
* What will your team do before we meet again?
* Is anything slowing your team down or getting in their way?
* Are you about to put something in another team’s way?

Sprint Planning Meeting
At the beginning of the sprint cycle (every 7–30 days), a “Sprint Planning Meeting” is held.

* Select what work is to be done
* Prepare the Sprint Backlog that details the time it will take to do that work, with the entire team
* Identify and communicate how much of the work is likely to be done during the current sprint
* Eight hour limit

At the end of a sprint cycle, two meetings are held: the “Sprint Review Meeting” and the “Sprint Retrospective”

Sprint Review Meeting

* Review the work that was completed and not completed
* Present the completed work to the stakeholders (a.k.a. “the demo”)
* Incomplete work cannot be demonstrated
* Four hour time limit

Sprint Retrospective

* All team members reflect on the past sprint
* Make continuous process improvements
* Two main questions are asked in the sprint retrospective: What went well during the sprint? What could be improved in the next sprint?
* Three hour time limit

Artifacts

Product backlog

The product backlog is a high-level document for the entire project. It contains backlog items: broad descriptions of all required features, wish-list items, etc. prioritized by business value. It is the “What” that will be built. It is open and editable by anyone and contains rough estimates of both business value and development effort. Those estimates help the Product Owner to gauge the timeline and, to a limited extent, priority. For example, if the “add spellcheck” and “add table support” features have the same business value, the one with the smallest development effort will probably have higher priority, because the ROI (Return On Investment) is higher.

The product backlog is the property of the Product Owner. Business value is set by the Product Owner. Development effort is set by the Team.

Sprint backlog

The sprint backlog is a document containing information about how the team is going to implement the features for the upcoming sprint. Features are broken down into tasks; as a best practice, tasks are normally estimated between four and sixteen hours of work. With this level of detail the whole team understands exactly what to do, and anyone can potentially pick a task from the list. Tasks on the sprint backlog are never assigned; rather, tasks are signed up for by the team members as needed, according to the set priority and the team member skills.

The sprint backlog is the property of the Team. Estimations are set by the Team. Often an according Task Board is used to see and change the state of the tasks of the current sprint, like “to do”, “in progress” and “done”.

Burn down

The sprint burn down chart is a publicly displayed chart showing remaining work in the sprint backlog. Updated every day, it gives a simple view of the sprint progress. It also provides quick visualizations for reference. There are also other types of burndown, for example the Release Burndown Chart that shows the amount of work left to complete the target commitment for a Product Release (normally spanning through multiple iterations) and the Alternative Release Burndown Chart, which basically does the same, but clearly shows scope changes to Release Content, by resetting the baseline.

It should not be confused with an earned value chart.