(n.) A boundary across which two independent systems meet and act on or communicate with each other. In computer technology, there are several types of interfaces.
    •    user interface - the keyboard, mouse, menus of a computer system. The user interface allows the user to communicate with the operating system. Also see GUI.
    •    software interface - the languages and codes that the applications use to communicate with each other and with the hardware.
    •    hardware interface - the wires, plugs and sockets that hardware devices use to communicate with each other.
(v.) To connect with or interact with by means of an interface.

Source: Webopedia