1. A terminal to provide a see-through input, the terminal comprising: a touchscreen to display a first application and a second application, to sense occurrence of a touch, and generate a touch signal in response to a sensed touch; and a control unit to determine whether the sensed touch is a general input for the first application or a see-through input for the second application according to the generated touch signal, and to execute a function of the first application according to the general input or a function of the second application according to the see-through input according to the determination, wherein a transparency of the first application is varied and the first application is displayed on the touchscreen to at least partially overlap the second application.