User stories (module)

A user story is a brief description of a requirement from the perspective of an end user. User stories specify the type of user, their goal and their motive. One or two sentences in length and written in first-person, everyday English typically in the format;

As a <<type of user>>, I want to <<achieve this goal>> so that <<this motive is satisfied>>.

The advantage of this format, compared to more traditional formats, is that it allows more flexible interpretation of unclear or changing requirements and vertical task breakdown (i.e. people can work on different layers of the same task simultaneously). One acronym used to try to write good user stories is INVEST;

• Independent: The user story should be self-contained, in a way that there is no inherent dependency on another user story.
• Negotiable: User stories, up until they are part of an iteration, can always be changed and rewritten.
• Valuable: A user story must deliver value to the end user.
• Estimable: You must always be able to estimate the size of a user story.
• Small: User stories should not be so big as to become impossible to plan/task/prioritize with a certain level of certainty.
• Testable: The user story or its related description must provide the necessary information to make test development possible.

Example: As a yunity user, I want to be able to create a profile so that my friends can identify me and strangers can recognize me.