The technical work that a development team performs in order to complete a product backlog item are defined as tasks. A scrum board is a visual board for creating and tracking tasks. There are two types of basic task, user can create for each User Story i.e. Task and Defect.
Tasks will be moved to different status lane (i.e. To Do, In Progress and Completed) as the member is progressing in a sprint. The one may also configure the task status lane from the Taskboard Configuration section, for instance: Code Review or Testing.