User InterfacesUser interfaces are designed for people to interact with technology.
Application Programming InterfaceAn API is an interface for software to control or communication with software.
Hardware InterfacesComputing hardware offer interfaces to be used by software or other hardware.
ServicesServices are offerings that have intangible qualities such as reliability or friendliness. In many cases, services are essentially interfaces between business entities, people and technology at various levels. For example, customer service is an interface between a business and customers.
A means of interaction, control or communication.