A variety of percussion instruments found around the world, especially in Native American cultures, Africa, South East Asia and Oceania.

Traditionally, a whole log was hollowed out through a narrow slit running the length of the log. The instrument would be hit with padded sticks to produce a range of penetrating musical notes, depending on where and how it was struck.

The type normally know as a slit drum has slits cut to form two tongues with different tones whereas the modern tongue drum has from 4 to 12 tongues carefully tuned to play harmonically.

These instruments are usually referred to as a type of drum, but are strictly idiophones rather than membranophones.