Fan Out allows you to run the same sequence of steps over each object in an array (or list) of objects. For example, you might want to query a segment of users from your database and send each user a message. To do this, you could use a PostgreSQL step to query your users, then a Fan Out step to iterate over each user, followed by a Sendgrid step to send each user an email.
To add a Fan Out to your workflow, click the "+" button in your workflow canvas and choose Fan Out from the sidebar. Then, click the dropdown button under "Fan out which array?" to invoke the variable menu and choose the array you want to fan out.
Any steps you add within a Fan Out will run for each object in the array passed into the Fan Out. To reference the object in the array from within a Fan Out, you can reference the Fan Out's
instance object from the variable menu.
Note that iterations within a Fan Out are executed in parallel, although your workflow will wait for all iterations to finish before proceeding to steps after the Fan Out.