Bongos are a pair of small drums joined together, one a bit bigger than the other, played with the hands, not sticks. You usually hold them between your knees, sitting down. The two drums give two pitches, so the player can tap out a pattern that jumps from high to low. They come from Afro-Cuban music and then travelled into jazz, pop, and school music rooms. People say 'the bongos' or 'a pair of bongos'; one drum of the pair can be called a bongo, but in real talk the plural is what you hear. The word is informal-neutral — music talk, not a fancy word. Do not mix them up with congas, which are taller drums you often play standing up.