Customer

A customer is somebody who receives customer service from a service deliverer.

Generally it is easier to see a customer as a person but sometimes an organisation can be a customer.  In most cases a customer or his or her organisation is paying directly or indirectly for the service that is being received.

If a customer is a private individual or comes from another organisation he or she is an external customer.  If a customer comes from another part of the same organisation he or she is called an internal customer.