Levels of Task Decomposition are hierarchically organized and subordinated items in a task decomposition design to define and display the amount of work that is required to perform parent or root tasks. Levels show the algorithm of performing root tasks and identify milestones, sub-tasks and goals.
There are 4 possible levels in task decomposition. These levels are described below:
- Level 1. Parent Task: top-level items in task hierarchy; they characterize identifiable and essential pieces of work to be done upon completion of sub-tasks and their goals at lower levels.
- Level 2. Milestones: scheduled stages or events that indicate completion of goals and sub-tasks; milestones do not consume resources and do not have duration. They just indicate completion status of related sub-tasks and goals.
- Level 3. Sub-tasks: simple activities and operations that produce observable and measurable end results related to broader outcomes of root tasks.
- Level 4. Goals: observable and measurable outcomes that are achieved within a more or less fixed timeframe and tracked by milestones.
In practice, task decompositions can be divided into 3 levels (Root Tasks-Milestones-Subtasks). The level "Goals" is often omitted. Goals are included in sub-tasks.