> For the complete documentation index, see [llms.txt](https://docs.appfarm.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.appfarm.io/library/action-nodes/block.md).

# Block

The Block action node can be used to group a set of action nodes and control their execution. 

### Properties

| Property           | Description                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| ------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **Execution Mode** | <p>There are three options:<br><br><strong>Sequential (default):</strong> When running in sequential mode, the action nodes behave as they would in any other block node.<br></p><p><strong>Parallel:</strong> All action nodes are executed in parallel. Useful when fetching data from multiple third parties. If one of the children fails, the entire block will fail. Any catch exception blocks added as direct children to the block will be ignored in this execution mode.<br></p><p><strong>First to finish:</strong> All children are executed in parallel, but the block will finish as soon as the first child is done. Note that all the siblings will still run until finished. Any errors occurring in any of the children will be ignored on block level. Any catch exception blocks added as direct children to the block will be ignored in this execution mode.</p> |


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