This is a technique that uses straightforward short sentences to describe the needs of a stakeholder. A user story also includes where the value in the feature it describes lies by including a reason for the requirement or need. The goal of user stories is to encourage simplicity and further conversation between members of the delivery team. 

A user story will always include information about who the feature is for, what function the feature performs, and why it is of value to the user. A common way to formulate a user story is "as a [role], I need to [what], so that [why]." 

Another format that is sometimes used is called the Gherkin format, which follows a "Given…, when…, then …." format.

User stories are an effective way of getting teams to understand the essence of a user's needs and acts as an effective trigger for further discovery and development.