Workflow 'expressions'

Noob question but I’ve not found anything helpful on the docs or on the internet so I have to ask here.
I see in various configurations the fields ‘expressions’ but there’s no syntax reference. I particularly need help with a syntax reference for the ‘expressions’ field in the workflow settings

It is fine, this is the purpose of the forum.

The expressions can be used to restrict workflows based on field values,


data.isConfirmed.iv === true