In BPMN, a task means an atomic business or activity that can not be divided any more.
Overview of Task
In BPMN specification, a task is defined as "Atomic Activity" and means a business or activity that can not be divided any more.
In other words, "a dividable activity" can be considered as a composite of multiple tasks. "A dividable activity" is sometimes called a sub-process or process.
Input/Output of Task
When processing a task, a participant in charge of the task is supposed to do the following.
- Receive "input information" from a participant executing upstream tasks. (Receive information to do its own task.)
- Deliver "output information" to a participant executing downstream tasks. (Append and deliver the information about its own outcome.)
In workflow research field, conceptually Workflow Engine, also called "BPM engine," mediates business information, and "each concrete task" (a task instance) is sometimes explicitly called "a work item."
From the perspective of a participant, for example, it can be said that his/her "TODO list" includes work items, such as "reviewing a report of October" and "settling the application for days off in August." In this case, "the TODO list" is called a work list or a work item list.
In addition, not only "a human" but also "an information system (a computer)" can be considered as a participant.
Task level Analysis of Outcome
In BPM activities, a task level analysis of the outcome, in addition to the analysis in process data level, is often imperative.
More specifically, analyzing the outcome of each task (a completed work item) not only helps us grasp "the number of tasks processed per day" and "the average time taken for the task" but also could help us identify:
- "a skilled participant for a certain task" on average,
- and the most appropriate participant for each type of work items.