Roles Main article: The Chicken and the Pig

Several roles are defined in Scrum; these are divided into two groups; pigs and chickens, based on a joke about a pig and a chicken.[5]

A pig and a chicken are walking down a road. The chicken looks at the pig and says, "Hey, why don't we open a restaurant?" The pig looks back at the chicken and says, "Good idea, what do you want to call it?" The chicken thinks about it and says, "Why don't we call it 'Ham and Eggs'?" "I don't think so," says the pig, "I'd be committed but you'd only be involved."

So the "pigs" are committed to building software regularly and frequently, while everyone else is a "chicken": interested in the project but really irrelevant because if it fails they're not a pig; that is, they weren't the ones that committed to doing it. The needs, desires, ideas and influences of the chicken roles are taken into account, but not in any way allowed to affect or distort or get in the way of the actual Scrum project.

[edit] "Pig" roles

Pigs are the ones committed to the project in the Scrum process; they are the ones with "their bacon on the line".

Product Owner

The Product Owner represents the voice of the customer. They ensure that the Scrum Team works with the right things from a business perspective. The Product Owner writes user stories, prioritizes them, then places them in the product backlog.

ScrumMaster (or Facilitator)

Scrum is facilitated by a ScrumMaster, whose primary job is to remove impediments to the ability of the team to deliver the sprint goal. The ScrumMaster is not the leader of the team (as they are self-organizing) but acts as a buffer between the team and any distracting influences. The ScrumMaster ensures that the Scrum process is used as intended. The ScrumMaster is the enforcer of rules.

Team

The team has the responsibility to deliver the product. A team is typically made up of 5–9 people with cross-functional skills to do the actual work (designer, developer, tester, etc.).