A service is any activity or benefit that one party can give to another that is essentially intangible and does not result in the ownership of anything. Its production may or may not be tied to a physical product
Kotler, P., & Armstrong, G. (1999). Principles of marketing (8th , ed.). Upper Saddle River, N.J. ; London: Prentice Hall International.

Service Design

'''Service Design''' is the activity of planning and organising people, infrastructure, communication and material components of a service in order to improve its quality, the interaction between service provider and customers and the customer's experience.
The increasing relevance of the service sector, both in terms of people empoyed and economic importance, requires services to be accurately designed. The design of the service may involve a re-organisation of the activities performed by the service provider (Back office) and/or the redesign of time and place in which customers come in contact with the service (Front office).