ITSM or IT Service Management has become a catch-all term used when referencing any IT Service provided to your internal customers (employees) and external customers or business partners.
ITSM originally focused on the services provided by IT support, the IT help desk or later the IT service desk. Unlike network management and IT systems management, which have a technology-oriented approach, ITSM focuses on customer needs and IT services for the customers. It is the processes and procedures needed to plan, design, deliver, operate and control information technology.
You can learn more about all things ITSM on the ServiceMuse ITSM channel