The team decides about the work
In Scrum, after the Sprint Planning, the Development Team starts to work on the Sprint Backlog items. In fact, each member of the team analyzes the items in the Sprint Backlog. Afterwards, the team decides who will work on what tasks.
Even if team members can work individually on a specific task, nobody has the ownership of a specific item. This helps to increase transparency and avoid individual boundaries.
Useable increments within short Sprints
The heart of Scrum is the Sprint. During each Sprint the Development Team creates a potentially releasable product increment. In addition, the increment has to be in useable conditions at the end of the Sprint.
Moreover, one of the primary responsibilities of the Scrum Master is to coach the Development Team in working to produce a useable Product Increment within short Sprints. In fact, when the increment is ready, the Product Owner can decide to release it or not.
Even if Scrum is a new framework, the traditional job of project planning and control is still performed. The difference between traditional and Scrum planning is that the latter is continuous. Another difference is that the entire team performs the planning and control. So, these activities are performed by the team and not by project managers.
The Development Team plans how to perform the work of the Sprint. It decomposes the work into work units. The first decomposition happens in Sprint Planning. When the work is done, the team inspects the work since the last Daily Scrum and forecasts the next Sprint’s work.
Keep in mind
Even though, there is no long-term planning in Scrum, the planning is done for short-term Sprints. Moreover, continuous planning allows the team to look for changes, and respond to them, on a timely manner.