The sound emitted by crickets is commonly referred to as chirping; the scientific name is stridulation. Only the male crickets chirp. The sound is emitted by the stridulatory organ, a large vein running along the bottom of each wing, covered with "teeth" (serration) much like a comb. The chirping sound is created by running the top of one wing along the teeth at the bottom of the other wing. As he does this, the cricket also holds the wings up and open, so that the wing membranes can act as acoustical sails. It is a popular myth that the cricket chirps by rubbing its legs together.
There are four types of cricket song: The calling song attracts females and repels other males, and is fairly loud. The courting song is used when a female cricket is near, and is a very quiet song. An aggressive song is triggered by chemo-receptors on the antennae that detect the near presence of another male cricket and a copulatory song is produced for a brief period after a successful mating.