ITIL stands for The Information Technology Infrastructure Library; it is generally grouped with ITSM. ITSM (IT Service Management) is an approach of organizing and administrating large scale technology systems by centering the management decisions around the customer's viewpoint of the contribution of IT and interconnected systems to the actual business. It basically is a framework which is designed in a way so that it can be used for the interaction of IT and business users. 

Some people consider both of these terms as synonyms which is entirely incorrect approach. In fact, ITSM is a module of ITIL.ITIL  change management focuses on IT services – it is considered as a source of industry-standard best practices that give a common ground for various components within a business to talk about service management. 

The particular management service exists as a series of published books that each covers a crucially important area of IT Management.  The designed framework informs an organization what is to be done and then it depends on the organization to work out how to do it.

The IT Service Management within the ITIL is divided into two separate disciplines:

·         Service Support

·         Service Delivery  

Service support of ITIL  is basically responsible for keeping control of all configuration changes which are made in management database. The particular service notice all changes occurred within the live environment – test or itil training environment. ITIL service deals with the user of actual services – the service actually depends on the need of user to have proper access to the services that are required by them. The user’s point of contact is the service desk of organization which is responsible for five different kinds of management to bring the issue to resolution. 

On the other hand, the Service Delivery Discipline is related to practically reviewing the services are constantly provided to business users of IT.

The ITIL Change Management consists of mounting business justification. This is a expansion of scope from other perceptions of Change Management.