1. A terminal comprising: a processor comprising an image acquirer configured to acquire, from a camera, first face image data from a first image at a first time while content is being displayed, and acquire, from the camera, second face image data from a second image at a second time while the content is being displayed; a face recognizer configured to recognize a first face included in the first face image data and a second face included in the second face image data; a face change detector configured to detect whether the first face is different from the second face; a contact searcher configured to, in response to the detection that the first face is different from the second face, search a contact corresponding to the second face; and an information transmitter configured to transmit, to the searched contact, content usage information comprising the content or information used to acquire the content.