Form Actions are events that trigger automatically when a form is submitted. As soon as a form is submitted, the Actions page will determine what happens next.
This could be one or multiple of the following actions;
Insert / Update Database Record
Email PDF with Attachments
Post XML (deprecated - use webhooks)
Create CRM Task
Update CRM Client
Create CRM Lead
Insert / Update Aggregate Source
Create CRM Client
Modify Form Status
If a form is connected to a job the form actions will trigger once the job is completed.