A linkage between two things. A user interface is the system of controls with which the user controls a device. Two devices are said to be interfaced when their operations are linked electronically. An interface box is often required to convert signals from one form to another

Taken from the words Internet and Face. It refers to someone who is a lot better looking on the internet (eg Facebook Profile Picture) than they are in real life.

A person who doesn't like it anally. He(usually a he) enjoys it interface style