The complete framework of ITIL is based on service lifecycle. Each lifecycle defines certain processes for effective service management.
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Service lifecycle helps to amplify the service management approach and to achieve a better understanding of its structure. In the coming chapters, we will be discussing all such lifecycles individually with their processes and functions.
Processes and Functions
There are 26 processes and 4 functions in ITIL V3. These processes and functions are discussed in detail with each service lifecycle in further chapters.
Process
A process defines policies, standards, guidelines, activities, and work instructions. It takes some defined inputs to produce desired results.
Functions
A function is defined as group of people or tools required to carry out one or more processes and activities.