A hi-hat (hihat, high-hat, etc.) is a combination of two cymbals and a foot pedal, all mounted on a metal stand. It is a part of the standard drum kit used by drummers in many styles of music including rock, pop, and blues. Hi-hats consist of a matching pair of small to medium-sized cymbals mounted on a stand, with the two cymbals facing each other. The bottom cymbal is fixed and the top is mounted on a rod which moves the top cymbal towards the bottom one when the pedal is depressed (a hi-hat that is in this position is said to be “closed” or “closed hi-hats”). (source)