This is a function available in Salesforce for contact roles on opportunities (deals) where you can specific who is the primary contact out of all the contact roles added and it adds a specific label to show this in the role list; this would be nice to have something similar instead of having to create multiple contact roles just to have 'role 1' and 'role 1 primary' ... times however many roles are needed to accommodate this.  Screenshot is just an example of the indicator referring to.