# Trigger It helps you start automated actions based on real-time activities such as new messages, form submissions, or updates in integrated systems.
Trigger component in the Fastn flow editor canvas
* You can add this component by searching for **Trigger** in your flow. Once added, you’ll first need to **select an app** from the available list or search for the required one.
App selection panel showing available apps for the Trigger component
* After selecting the app, connect and authenticate your account to enable access.
Account authentication dialog for connecting an app to the Trigger
* After saving, the Trigger will automatically listen for the selected event. {% hint style="info" %} Based on the selected app, a list of **Trigger events** will appear. {% endhint %}
List of available trigger events for the selected app
> In the case of Slack, when a message is posted in the specified channel, the trigger will activate and send a message from Fastn to that channel. * Next, select the **account ID** associated with the connection, for example, *Fastn*. * In the **Headers** section, add the required key–value pairs for authentication or configuration. Once you’ve entered all details, click **Save** to finalize this step.
Trigger configuration panel with account ID selection and headers key-value pairs
* You can choose the event that should start your flow. For example, when integrating with Slack, you can select the **Message Posted** trigger event.
Selecting the Message Posted trigger event for Slack integration
* You can test this step by clicking the **Test** button in the top right corner. > The console will display the result, and you’ll see the message sent to your selected Slack channel.
Test results in the console showing the Slack trigger response