Definition of Done (DOD) in the Scrum is a predefined list of requirements that must be met before a task or a sprint can be considered completed. The dod serves as a common understanding of the entire development team and ensures that all requirements are fully met before a task is considered to be considered.
This is important to ensure that all requirements are met and that the result is of high quality and functional. The DOD can include technical requirements, quality requirements and requirements for usability.
In Scrum is an important part of quality management and helps to avoid misunderstandings and errors by giving a clear idea of what is considered completed.