There are also several types of rhythmic wood instruments. Here are several examples of these and their performing techniques.
Castanets originate from Spain, from Flamenco music. They are hollowed pieces of flat wood,tied together with a thin rope, hung on the thumb and hit with the fingers. The orchestral variety of castanets are modified and either have handles or are fixed to a wooden board and are sprung together, to make them easy to play. The Guiro is a Latin American instrument, made from a hollowed gourd with a serrated shell, which can be scraped up and down or tapped rhythmically. You can also buy metal guiro now. The Vibraslap mimics the sound of a rattled jawbone, or quijada. The player strikes the ball and the resulting vibration shake small free-moving rivets in the box and the woodblock, as it name suggests, is a piece of wood, which has been hollowed out. (Although, these days, woodblocks can also made of plastic).
Photograph courtesy of Bell Percussion