# System events

It is possible to connect a machine workflow to a specific event that occurs on the Flow server.

Examples of this can be when a user is added to Flow a machine workflow that sends an email to the user will be executed, or when a user steps over a log point in a workflow a machine workflow will be executed that commit the data to an appropriate data source. Connect a workflow to a system event by either *Pick* an already existing machine workflow or click on *New* to create and connect a new machine workflow. Choose a user that will be the executor of the machine workflow.

> Observe that only machine users will appear in the list of users that can execute a system event.

> Create system event workflows with the *New* button to get event specific parameters generated in the start step.

System events that is possible to connect a machine workflow to:

* **Start workflow:** The machine workflow will be executed when all workflows is started.
* **End workflow:** The machine workflow will be executed when all workflows is ended.
* **Add user:** The machine workflow will be executed when a user is added.
* **Remove user:** The machine workflow will be executed when a user is removed.
* **Log point:** The machine workflow will be executed when a log point is stepped over in a running workflow application, read more about log points [here](https://help.novacuraflow.com/development/flow-studio/applications/workflow/log-point).
* **Handover:** The machine workflow will be executed when the workflow hands over to another swim lane.
* **Device Status Changed:** The machine workflow will be executed when a new device request is sent to the Flow environment, read more about device management [here](https://help.novacuraflow.com/development/flow-studio/environment/devices).
* **Help Request:** The machine workflow will be executed when a new help request is registered, read more about help request [here](https://help.novacuraflow.com/development/flow-studio/monitoring/help-requests).