For a service to be successfully delivered, it is important that a set of activities are performed either manually or automated, to complete a process that produces a defined output. To continually ensure that all the activities are performed effectively, it is imperative that, organizations clearly define the roles and responsibilities of every individual and component that performs the activities. Once we’ve clearly defined the roles and responsibilities, we’d then need to group them based on the type of the activity performed, the frequency and various administrative purposes. A ‘Function’ in ITIL is defined as ‘A group of people and the tools or other resources they use to carry out one or more processes or activities.’ Meaning, any tool or other resources like applications, servers, and routers, switches that are used to complete a process or an activity and the people who perform the activity are considered a function. ITIL classifies all such functions into four major categories: Service Desk, Technical Management, IT Operations Management and Application Management.
Example: The operator receives a phone call requesting for a Home Delivery, wherein the operator starts a process, names order taking using the help of an application and takes the order. The operator then communicates to the chef using another application, requesting the order be prepared. Once the order is prepared and packed, the chef communicates to the operator that the delivery is ready and the operator then communicates to the delivery boy that an order needs to be delivered to a specified location. Here, both the people and the applications are both part and parcel of a function, while one is a manual function the other is an automated function.