What is ITIL? Explain?

ITIL, formerly an acronym for Information Technology Infrastructure Library, is a set of practices for IT Service Management (ITSM) that focuses on aligning IT services with the needs of business.

OR

ITIL is an integrated set of best-practice processes for delivering IT services to customers. The primary focus is to maximize value to customers (the business) by aligning IT resources with business needs. 

Since V3, ITIL has been narrowed down to 5 “lifecycle” phases:

1. Service Strategy – focusing on understanding customer needs, directions, requirements, helping improve IT over time
2. Service Design – focusing on turning strategies for services into a detailed Service description, not just the technology.
3. Service Transition – focusing on building, validating, and delivering new and changed services to customers
4. Service Operations – focusing on the day-to-day care and feeding of services
5. Continual Service Improvement – focusing on identifying and managing incremental improvements to services

One of the reasons for ITIL’s widespread adoption is the active involvement of a global and diverse community of IT professionals, consultants, trainers, and professional organizations.

DETAILED DESCRIPTION FROM WIKI :

1) Service strategy

The center and origin point of the ITIL Service Lifecycle, the ITIL Service Strategy (SS) volume,^[5] provides guidance on clarification and prioritization of service-provider investments in services. More generally, Service Strategy focuses on helping IT organizations improve and develop over the long term. In both cases, Service Strategy relies largely upon a market-driven approach. The Service Strategy lifecycle stage is often considered as the core of the service lifecycle. In Service Strategy stage, the strategic approach for the whole lifecycle is identified to provide values to the customers through IT service management. Key topics covered include service value definition, business-case development, service assets, market analysis, and service provider types. List of covered processes:

• Strategy management for IT Services
• Service portfolio management
• Financial management for IT services
• Demand management
• Business relationship management

For candidates in the ITIL Intermediate Capability stream, the Service Offerings and Agreements (SOA) Qualification course and exam are most closely aligned to the Service Strategy (SS) Qualification course and exam in the Lifecycle stream.

2) Service design

The Service Design (SD) volume^[6] provides good-practice guidance on the design of IT services, processes, and other aspects of the service management effort. Significantly, design within ITIL is understood to encompass all elements relevant to technology service delivery, rather than focusing solely on design of the technology itself. As such, service design addresses how a planned service solution interacts with the larger business and technical environments, service management systems required to support the service, processes which interact with the service, technology, and architecture required to support the service, and the supply chain required to support the planned service. Within ITIL, design work for an IT service is aggregated into a single Service Design Package (SDP). Service design packages, along with other information about services, are managed within the service catalogues.

List of covered processes:

1. Design coordination
2. Service catalogue management
3. Service-level management
4. Availability management
5. Capacity management
6. IT service continuity management
7. Security management
8. Supplier management

A model used to help define roles and responsibilities in service design is a RACI matrix (Responsible, Accountable, Consulted and Informed).

3) Service transition

Service transition (ST), as described by the ITIL service transition volume,^[7] relates to the delivery of services required by a business into live/operational use, and often encompasses the "project" side of IT rather than business as usual (BAU). This area also covers topics such as managing changes to the BAU environment.

List of ITIL processes in service transition:

1. Transition planning and support
2. Change management
3. Service asset and configuration management
4. Release and deployment management
5. Service validation and testing
6. Change evaluation
7. Knowledge management

4) Service operation

Service Operation (SO) aims to provide best practice for achieving the delivery of agreed levels of services both to end-users and the customers (where "customers" refer to those individuals who pay for the service and negotiate the SLAs). Service operation, as described in the ITIL Service Operation volume,^[8] is the part of the lifecycle where the services and value is actually directly delivered. Also the monitoring of problems and balance between service reliability and cost etc. are considered. The functions include technical management, application management, operations management and service desk as well as, responsibilities for staff engaging in Service Operation.

Processes

1. Event Management
2. Access Management
3. Request Fulfillment
4. Problem Management
5. Incident Management

Functions

1. Service Desk
2. Technical Management
3. Application Management
4. IT Operations Management

Service desk

The service desk is one of four ITIL functions and is primarily associated with the Service Operation lifecycle stage. Tasks include handling incidents and requests, and providing an interface for other ITSM processes. Features include:

• single point of contact (SPOC) and not necessarily the first point of contact (FPOC)
• single point of entry
• single point of exit
• easier for customers
• streamlined communication channel

Primary purposes of a service desk include:

• incident control: life-cycle management of all service requests
• communication: keeping a customer informed of progress and advising on workarounds

The service desk function can have various names, such as:

• Call center: main emphasis on professionally handling large call volumes of telephone-based transactions
• Help desk: manage, co-ordinate and resolve incidents as quickly as possible at primary support level
• Service desk: not only handles incidents, problems and questions but also provides an interface for other activities such as change requests, maintenance contracts, software licenses, service-level management, configuration management, availability management, financial management and IT services continuity management

The three types of structure for consideration:

• Local service desk: to meet local business needs – practical only until multiple locations requiring support services are involved
• Central service desk: for organizations having multiple locations – reduces operational costs^{[citation needed]} and improves usage of available resources
• Virtual service desk: for organizations having multi-country locations – can be situated and accessed from anywhere in the world due to advances^[when?] in network performance and telecommunications, reducing operational costs^{[citation needed]} and improving usage of available resources

5) Continual service improvement (CSI)

Continual service improvement, defined in the ITIL continual service improvement volume,^[9] aims to align and realign IT services to changing business needs by identifying and implementing improvements to the IT services that support the business processes. It incorporates many of the same concepts articulated in the Deming Cycle of Plan-Do-Check-Act. The perspective of CSI on improvement is the business perspective of service quality, even though CSI aims to improve process effectiveness, efficiency and cost effectiveness of the IT processes through the whole lifecycle. To manage improvement, CSI should clearly define what should be controlled and measured.

CSI needs upfront planning, training and awareness, ongoing scheduling, roles created, ownership assigned,and activities identified to be successful. CSI must be planned and scheduled as process with defined activities, inputs, outputs, roles and reporting. Continual Service Improvement and Application Performance Management (APM) are two sides of the same coin. They both focus on improvement with APM tying together service design, service transition, and service operation which in turn helps raise the bar of operational excellence for IT.^[13]

Improvement initiatives typically follow a seven-step process:

1. Identify the strategy for improvement
2. Define what you will measure
3. Gather the data
4. Process the data
5. Analyse the information and data
6. Present and use the information
7. Implement improvement