# Process workflow
A process is built as a workflow made of multiple modules.
The workflow controls how modules are executed, handling:
* parallel execution
* conditions (branching)
* loops (repetition)
This keeps control logic outside individual modules (sometimes called blocks), so each module stays focused on a single task.
## Module Types
There are three kinds of modules.
* 
Script
A Script module contains the actual commands to run.
Use it to define the step-by-step actions of your protocol.
* 
Loop
A Loop module repeats one or more modules.
Use it when a part of the protocol must run multiple times (for example: iterating over modules or repeating a some step).
* 
Conditional
A Conditional module creates a branching point in the workflow.
Depending on the defined criteria, the process follows one branch or another.
## Why use workflows?
Technically, you can implement loops and conditionals inside a single Script module using Python packages and native functions.
However, we recommend using the workflow approach because it makes protocols:
* easier to read and maintain
* more modular and reusable
* better structured (logic is explicit in the workflow)
## Example
In the example above, you can follow how the workflow is executed:
**1) Parallel execution (fan-out)**
After *modules 1, 2*, and *7*, the workflow splits into multiple branches.
This means the next connected modules can run in parallel (when they are independent).
**2) Loop execution**
The module *loop_1* repeats a part of the workflow.
In this example, it triggers the repeated execution of the branch that starts at *module 2*.
**3) Conditional execution (branching)**
The module *conditional_1* chooses one branch based on the condition criteria.
Here, it selects between the branch starting at *module 5* or *module 6*.
**4) Synchronization (wait / join)**
Some modules only start when all required input branches have finished.
For example, *module 11* waits until every incoming branch completes before it begins execution.
## Building a module
To create a new module, click New Module.
A window like the one below will open:
### Required information
Fill in the following fields:
* **Module name**
A unique name that identifies the module in the workflow.
* **Block type** (Choose the module type):
* Script
* Loop
* Conditional
* **Number of inputs**
How many modules will connect into this module.
This is used only for layout/design in the workflow editor (it does not change the execution logic).
* **Script path**
The location of the script file associated with this module.
#### Script options
You can either:
* create a new script for this module, or
* upload an existing script.
#### Saving
When you click Save, the script is stored automatically in the project directory using this structure:
```
...\ \ \ module_name.py
```
Note: The saved filename is based on the module name.