This document provides an overview of ITIL (IT Infrastructure Library), a framework for IT service management best practices. ITIL describes processes, functions, and roles involved in delivering and managing IT services. It is organized into 5 phases - Service Strategy, Service Design, Service Transition, Service Operation, and Continual Service Improvement. The document explains each phase and lists the 26 processes that are part of ITIL. Adopting ITIL helps organizations reduce costs, streamline processes, and improve IT services, customer satisfaction, and productivity.