5 December 2023 | Updated on 25 July 2024

The ITIL® 4 dictionary: Explore the key terms and concepts of the methodology

Whether you are an experienced IT service management professional or new to the industry, training in ITIL® 4 will introduce a wealth of new language and concepts. To help you understand this key term...

ILX Team
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Whether you are an experienced IT service management professional or new to the industry, training in ITIL® 4 will introduce a wealth of new language and concepts. To help you understand this key terminology we’ve curated a list of the core definitions you need to learn before you take your exam.

ITIL 4 key terms

  • IT Service Management (ITSM): Refers to the implementation and management of IT services in line with the organisation’s needs and objectives. It encompasses the policies, processes and procedures required to design, deliver, manage, and improve IT services
  • Service: In ITIL 4, a service is a means of delivering value to customers by facilitating desired outcomes
  • Configuration item (CI): A configuration item is any component or asset that needs to be managed in order to deliver IT services
  • Incident: An incident refers to any unplanned interruption or reduction in the quality of an IT service
  • Problem: A problem is the underlying cause of one or more incidents
  • Change: A change refers to the addition, modification, or removal of any configuration item within the IT infrastructure
  • Guiding principles: ITIL 4 introduces seven guiding principles that organisations should follow to guide their decisions and actions. These principles include focus on value, start where you are, progress iteratively with feedback, collaborate and promote visibility, think and work holistically, keep it simple and practical, and optimise and automate
  • Practices: ITIL 4 includes 34 practices that organisations can adopt to improve their service management capabilities. These practices fall into three categories general management practices, service management practices and technical management practices
  • Four dimensions model: The four dimensions model provides a comprehensive view of service management, helping organisations to consider various aspects and perspectives when delivering a service. The four dimensions are organizations and people, information and technology, partners and suppliers, and value streams and processes. While external perspectives are analysed using PESTLE
  • Service value system (SVS): A model that represents the components and activities necessary for creating value through IT service management. The SVS encompasses the guiding principles, practices and continual improvement of services
  • Service value chain (SVC): The key activities an organisation performs to deliver value to its customers. There service value chain consists of six activities, engage; plan; improve; design and transition; obtain/build; and deliver and support
  • Service Level Agreement: A formal agreement between a service provide and a customer that outlines the expected level of service, including performance targets, responsibilities, and metrics for measuring service quality
  • Experience Level Agreement (XLS): Designed to shift the focus from traditional service level agreements and key performance indicators (KPIs) to a more customer-centric approach. XLAs are used to measure and improve the overall experience of users and customers with IT services

How do I start training?

Certifying in ITIL 4 will provide a structured approach to IT service management that will improve your current skillset, progress your career and benefit your organisation.

For those new to the methodology, you will need to begin with the ITIL 4 Foundation qualification, once you’ve passed your Foundation exam, there are multiple courses available to help you develop your knowledge further. Learn more about the ITIL 4 qualifications available.