The use of the term ‘Service' is somewhat overloaded. Everyone will have heard or used the terms Business Services, IT Services, Software Services, and now Cloud Services, and yet often there is much confusion and misunderstanding in their use. As my colleague David Sprott suggested in a CBDI Journal Report, "Everything is a Service" . In that report David suggested that the idea that "everything is a service" could be developed to clarify the taxonomy for Cloud Services and Services in the form of a Unified Service Model that would deliver convergence of business and IT perspectives.Consequently, I have penned a research note available on Everware-CBDI site that provides a concept model that explores the basic concepts of Service and Service-Orientation taking into account this broad perspective including Business Service, IT Services, Software Services, Cloud Services and even Human Services.

What Is a Service?
Readers will be familiar with the basic concept of a Service.  That is, where someone or something provides a Service to another.The notion that someone or something offers a Service to another introduces the concept of the Service Provider and Service Consumer as illustrated in Figure 1. A Service Provider is as its name suggests is someone or something that provides a Service. And the Service Consumer is someone or something that consumes or uses the Service.Real World Example: A logistics company provides a Goods Delivery Service. This is used by a manufacturer to ship goods to its clients.The logistics company is the Service Provider.  The manufacturer is the Service Consumer.

Figure 1: Service Consumers and Providers

Capability
The reason a Service Provider is able to provide the Service is because they possess the Capability required to do so.A Capability is the power or ability to perform some function. We may think of a person, an organization or something (a machine, or some technology) as having the Capability to perform some function. In turn the Service Provider may offer their Capability to others, in the form of a Service. Meanwhile, a Service Consumer is someone or something that requires the Capability. Hence we may understand a Service as a Capability offered by a Service Provider to a Service Consumer Real World Example: A logistics company has the Capability to deliver goods.  Therefore it is able to offer a Goods Delivery Service to others.

Figure 2: Service and Capability

Types of Service
In the real world example used so far, a logistics company provides a Goods Delivery Service to a manufacturer.This may be referred to as a Business Service, as it reflects the nature of the activity - where one business is providing its services to another. It is also normally offered on a commercial basis, and may be considered as a Business Service because business is being transacted through its use.We can think of Business Service as a particular type of Service.Other types of Service commonly used in an IT context are:

• IT Service, where the IT department (or third party) provide a service to the business
• Software Service, where a unit of software provides a service to another software unit
• Cloud Service, where a Software Service is provided over a network and conforms to cloud computing principles

We can even consider a Human Service where one person provides services to another and relies upon human resources to provide the required Capability.Regardless of the type of Service, the concepts discussed so far still hold true.Whether it is a Business Service, an IT Service or a Software Service, Cloud Service, or a Human Service, they still all provide a Capability, and are all provided by a Service Provider and used by a Service Consumer.

Figure 3: Types of Service showing different forms of Service Provider and Consumer