Radio drama is a dramatized performance broadcast on radio using only sound. It relies on codes and conventions like sound effects, genre, storyline, characters, and accents to help listeners imagine the performance. Sound effects and accents provide context and help listeners visualize characters. The most crucial element is the storyline, which must keep listeners interested and consistent. Radio dramas may feature a cast of actors each playing a character, or one actor playing multiple roles using different voices and accents.