The basic unit of agile development is the sprint (or iteration, in more general) the ability to take a set of user stories from the backlog and refine, code, test, and accept those stories into a new integrated baseline within a fixed timebox. The goal of each sprint is the same to build an increment of potentially shippable code that is of value to the users.

A sprint is typically between one to four week long, during which the team completes the work defined in the sprint backlog (see the next section).