In Agile software development, a sprint is a short, time-boxed period when a Scrum team works to complete a set amount of work. Sprints are typically one to four weeks long, and the number and length of sprints should be determined at the beginning of the project. During a sprint, the team works to create new features based on the user stories and backlog, and the work is done in iterations to be more collaborative and adaptive than traditional planning methods. The sprint is the Scrum event that encompasses all of the other Scrum events, and all the work necessary to achieve the product goal, including Sprint Planning, Daily Scrums, Sprint Review, and Sprint Retrospective, happens within sprints. The sprint goal is the single objective for the sprint, and it provides flexibility in terms of the exact work needed to achieve it. Sprint planning is a collaborative effort between the product owner, Scrum master, and development team to choose the right work items for a sprint. During a sprint, the team checks in during the daily scrum, or standup, about how the work is progressing, and after a sprint, the team demonstrates what they’ve completed during the sprint review. Sprints help teams follow the Agile principle of "delivering working software frequently," as well as live the Agile value of "responding to change over following a plan".