How many reeds (musical mouthpiece) are there on the Scottish Great Highland bagpipe?

The Great Highland bagpipe is a type of bagpipe native to Scotland, and the Scottish analogue to the Great Irish Warpipes. It has acquired widespread recognition through its usage in the British military and in pipe bands throughout the world.

The bagpipe is first attested in Scotland around 1400, having previously appeared in European artwork in Spain in the 13th century. The earliest references to bagpipes in Scotland are in a military context, and it is in that context that the Great Highland bagpipe became established in the British military and achieved the widespread prominence it enjoys today.

The Great Highland bagpipe is classified as a woodwind instrument, like the bassoon, oboe, and clarinet. Although it is further classified as a double-reed instrument, the reeds are all closed inside the wooden "stocks", instead of being played directly by mouth as most other woodwinds are. The Great Highland bagpipe actually has four reeds: the chanter reed (double), two tenor drone reeds (single), and one bass drone reed (single).

A reed is a thin strip of material that vibrates to produce a sound on a musical instrument. Most woodwind instrument reeds are made from Arundo donax ("Giant cane") or synthetic material.