Scrum methodology defines three essential roles: the Product Owner, responsible for defining and prioritizing the product backlog to maximize value and meet stakeholder needs; the Scrum Master, who ensures the Scrum framework is understood and adhered to, facilitates team interactions, and removes impediments to progress; and the Development Team, comprising professionals who collaborate to deliver potentially shippable increments of the product during short, time-boxed iterations called Sprints. These roles collectively support transparency, collaboration, and adaptive problem-solving, essential for effective agile product development.

Scrum methodology involves several key tasks that facilitate effective project management and delivery.

Agile Scrum Tasks offer numerous benefits for project teams, aligning with the principles outlined in the SBOK guide. Firstly, they promote collaboration and transparency among team members, fostering a shared understanding of project objectives and progress. Additionally, Agile Scrum Tasks enable adaptability, allowing teams to respond quickly to changes in requirements or priorities. This agility leads to improved responsiveness to customer needs and increased customer satisfaction. Moreover, by breaking down work into manageable tasks and iterating frequently, Agile Scrum Tasks facilitate continuous improvement, enhancing product quality and team efficiency over time. 

Task planning and estimation are vital to developing products iteratively in accordance with the requirements specified in the Prioritized Product Backlog. The Scrum Team, in Task Estimation Meetings, estimates the effort required to accomplish each task in the Task List. This is an optional process that involves creating task estimates if the Scrum Team sees value in doing so. In this process, the Scrum Team estimates the effort required to accomplish each task in the Task List. Task estimates could either be determined at the beginning of the Sprint for all User Stories/tasks relevant to that Sprint, or for each task just before the team starts working on the particular User Story/task. The estimation can be done using the same methods that were used for the Estimate User Stories process.

During Task Estimation Meetings, the Scrum Team uses the Task List to estimate the effort required to complete a task or set of tasks and to estimate the people's effort and other resources required to carry out the tasks within a given Sprint. One of the key benefits of this technique is that it enables the team to have a shared perspective of the User Stories and requirements so that they can reliably estimate the effort required. The information developed in the Task Estimation Meetings is included in the Updated Task List and Updated Scrumboard. These are used to determine the velocity for the Sprint. In this workshop, the Scrum Team may use various techniques such as decomposition, expert judgment, analogous estimation, and parametric estimation. Task Estimation Meetings may also be combined with Task Planning Meetings.

To maintain relative estimation sizes and minimize the need for re-estimation, the team uses estimation criteria. Estimation criteria can be expressed in numerous ways, with two common examples being story points and ideal time. Story point values are used to represent relative or comparative effort to complete tasks. Whereas, ideal time normally describes the number of hours a Scrum Team member works exclusively on developing the project’s deliverables, without including any time spent on other activities or work that is outside the project. Estimation criteria make it easier for the Scrum Team to estimate effort and enable them to evaluate and address inefficiencies when necessary.

The output of task estimation is the Updated Task List. It is a list of tasks associated with the User Stories committed to in a Sprint. Typically, the accuracy of the estimates varies with team skills. The updated Task List is used by the Scrum Team during Sprint Planning Meetings to update the Sprint Backlog and to create the Sprint Burndown Chart. It is also used to determine if the team needs to reduce its commitment, or if they can take on additional User Stories during Sprint Planning for the next Sprint.