The Ultimate Glossary of Terms About IT Service Management - Please continue to add terms and definitions here to make it one stop shop for quick reference.
Software as a service (SaaS)
Information Technology Infrastructure Library (ITIL)
IT service management (ITSM)
Enterprise service management (ESM)
Incident management (IM)
Problem management (PM)
Change management (CM)
Asset management (CMDB)
Service level management (SLM)
Service request management (SRM)
Self-Service Portal (SSHD)
Service Catalog (SC)
Service Request Definition (SRD)
Knowledge base (KB)
Service Value System (SVS)
Service Value Chain (SVC)
Service Integration and Management (SIM)
Software as a service is a software licensing and delivery model in which software is licensed on a subscription basis and is centrally hosted.
SaaS is also known as “on-demand software” and Web-based/Web-hosted software.
SaaS is considered to be part of cloud computing, along with infrastructure as a service (IaaS), platform as a service (PaaS), desktop as a service (DaaS), managed software as a service (MSaaS), mobile backend as a service (MBaaS), data center as a service (DCaaS), integration platform as a service (iPaaS), and information technology management as a service (ITMaaS).
Source:-Software as a service - Wikipedia
To understand more from a simple analogy of buying a car, renting a car or travelling on a bus, check this interesting article:
This is an alternative, creative, and more practical jargon of ITSM: