What is service management?

What is service management?
ITIL defines a service as follows:
A service is a means of delivering value to customers by facilitating outcomes that customers want to achieve without the ownership of specific costs and risks.

Service Management is what enables a service provider to:
understand the services that they are providing from both a consumer and provider perspective;
ensure that the services really do facilitate the outcomes that their customers want to achieve;
understand the value of those services to their customers and hence their relative importance;
Understand and manage all of the costs and risks associated with providing those services.

The definition of Service Management is:
Service Management is a set of specialised organisational capabilities for providing value to customers in the form of services.