Examples of Functions in ITIL include software testers and programmers. However, in the overall ITIL process, many other teams can be included: for example, facilities management teams are Functions too. Within Functions, staff are assigned specific Roles; within Service Operation, for example, you'll find roles such as 1st Level Support, Facilities Manager and IT Operations Manager. These are all people you'd expect to find working on, or alongside, a help desk or service desk team.