The elements · 06 · 8 min
Activities
Where the work happens. The icon in the corner says how the work is done.
Five task types, one icon each: a person in a system (user), software (service), by hand (manual), a rule-based decision (business rule) and a message out (send).
The shapes above are all tasks. What separates them is how the work gets done: by a person in a system, automatically in software, by hand, as a rule-based decision, or as a message going out or coming in. The table makes the distinction precise.
| Type | How the work is done |
|---|---|
| User task | A person completes it in a system: a form in a task list |
| Service task | Automatically, in software: an API call, no human involved |
| Manual task | By hand, outside any system (unpacking a box) |
| Script task | Automatically, by a script the process engine runs |
| Business rule task | As a decision: a rule set (e.g. a DMN table) is evaluated |
| Send task | By sending a message to another participant |
| Receive task | By waiting for a message to arrive |
A clerk opens a form in the task list and approves an invoice.
Markers: the row along the bottom edge
Four markers on the bottom edge: sub-process (+), loop, parallel multi-instance (three vertical bars) and sequential multi-instance (three horizontal bars).
A sub-process (+) collapses detail onto another diagram. A loop repeats while a condition holds. Multi-instance runs once per item in a collection, three vertical bars for parallel, three horizontal for sequential.
After this module you can
- Pick the right task type for a given piece of work
- Use sub-processes and call activities to control detail
- Read loop and multi-instance markers