# Sub Process Task
The **Sub Process Task** is used to **invoke another process** from within a main process.\
It is represented by a **rectangular BPMN task node**, as shown below.
***
### Purpose
The **Sub Process Task** enables modular and reusable process design by allowing a main process to call **another process** (the sub process).
This approach is recommended when:
* A portion of the main process can stand alone
* The same logic is reused across multiple processes
* You want to improve readability and maintainability
By extracting repeated or complex logic into a separate process and calling it via a Sub Process Task, you achieve **better clarity, reusability, and easier maintenance**.
***
### Sub Process Node Configuration Overview
The Sub Process Task configuration panel contains **three tabs**, each responsible for a specific aspect of configuration:
1. **General**
2. **Business Object**
3. **Subprocess**
Each tab is described below.
***
### General Tab
The **General** tab contains basic metadata for the Sub Process Task, such as:
* Task name (title)
* Task ID
* Description
These properties help identify and document the purpose of the task within the process flow.
> Remember to click **Save Panel** to persist any changes.
***
### Business Object Tab
The **Business Object** tab is used to configure and map **input and output parameters** between:
* The main process
* The called sub process
This mapping ensures that:
* Required data is passed into the sub process
* Results are returned to the main process after execution
Business Object mapping is essential when the sub process depends on or modifies process data.
***
### Subprocess Tab
The **Subprocess** tab is used to select and configure the process that will be invoked.
#### Subprocess Properties
| Property | Mandatory | Default | Description |
| ------------ | --------- | ------- | ----------------------------------------------- |
| Process Name | Yes | — | Name of the process to be used as a sub process |
#### Available Actions
* **Open Subprocess**\
Opens the selected sub process for viewing or editing.
* **Open Mapping Parameter**\
Opens the **Mapping Parameter** screen to configure:
* Input parameter mapping
* Output parameter mapping
From the mapping screen:
* Click **Mapping Parameter Input** to map data passed *into* the sub process
* Click **Mapping Parameter Output** to map data returned *from* the sub process
> **Important**\
> Click **Save Panel** after completing configuration in this tab.
***
### Best Practices
* Use Sub Process Tasks to avoid duplicating logic
* Define clear input/output parameters for sub processes
* Keep sub processes focused on a single responsibility
* Reuse sub processes across multiple workflows where applicable
***
### Summary
The **Sub Process Task** enables structured, reusable workflow design in ONEWEB.
Key points:
* Calls another process from within a main process
* Improves modularity and clarity
* Supports full input and output parameter mapping
* Encourages reuse of common business logic
* Essential for scalable and maintainable process architectures
Using Sub Process Tasks effectively helps build **clean, reusable, and production‑ready business processes**.
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