In a contact centre, what do you call your 'frontline' versus 'backoffice' teams and what functions/activities do you associate to each group? Is there an industry standard approach to definition/titling of these roles?

In a contact centre, what do you call your 'frontline' versus 'backoffice' teams and what functions/activities do you associate to each group? Is there an industry standard approach to definition/titling of these roles?