The triangle is an idiophone type of musical instrument that is made of a bar of metal bent into a triangle shape. It is frequently used in music that comes from the Northeast of Brazil like forró, baião, frevo, and xaxado. The sound is produced by striking the triangle with a metal beater, giving a high-pitched, ringing tone. In Brazilian music the triangle is hooked over the hand so that one side can be damped by the fingers to vary the tone. By opening the hand an open sound is produced, by closing the hand an damped sound is produced.