Ear coupling describes the way in which headphones or earphones stay attached to, or inside, the ear. There are three common types of ear coupling: circumaural, supra-aural and intra-aural. Circumaural headphones enclose your ears with large pads that suppress external noise. Supra-aural headphones are typically more lightweight and sit on top of the ears with small pads. Intra-aural headphones come in two basic designs and neither style sits on the head itself. The first are ear buds, which sit just outside of the ear canal, on top of your ear lobes. The second type is actually inserted directly into the ear canal and offers some external noise suppression.