Triggers are special plugins that are used in the properties of a workflow and check a specific condition which returns a "True" or "False" value. If a "True" value is returned the workflow is triggered (started).

Triggers are added to a worklfow by dragging & dropping a trigger from the "Triggers" section in the "Plugin Library" to the workflow and connecting the trigger-icon to "Start". This way multiple triggers can be connected to "Start" and if any of the triggers returns "True" the workflow is triggered (started).