Difference between Session Type Code And Service Code

Question: What is the difference between Session Type Code and Service Code? 

The Session Type code is a number associated with the Session Type Description this in turn creates that picklist your clinicians would see when creating an individual or group note. 

The Service Code is associated with the billing codes picklist which connects to a Transaction Type of Charge, Customer Payment, Discount, Write-Off, Collection-Out, Refund used by Billing. Your Biller would go to Setup -->Billing - Service to set up the service codes