Roles, artefacts, events, and the Guide-accurate answers to the definitional questions asked first.
3 questions in Agile, Scrum & Delivery.
Scrum defines three accountabilities (Product Owner, Scrum Master, Developers), five events inside the Sprint container, and three artefacts each carrying a commitment. Each event exists to force one specific inspect-and-adapt decision, and most workplace practices sit outside the framework entirely.
The Definition of Done is one shared quality standard every increment must meet, owned by the Scrum Team unless the organisation mandates a stricter minimum. An item that misses it is not partially done: it returns to the Product Backlog rather than being released or presented as complete.
Scrum's Sprint assumes work that can be planned a fortnight ahead, held stable for that fortnight, and shaped into a goal worth committing to. Where one of those fails - interrupt-driven support, single-item research, hard external gates - a flow-based approach fits better.