The Didgeridoo is a wind instrument developed by indigenous Australians of Northern Australia around 1500 years ago. The modern day didgeridoo is 3-10 feet long, most being around 4 ft. They are usually made from hardwoods, such as eucalyptus or bamboo. The mouthpiece is usually covered in beeswax to soften it. They are played by constant vibration of the lips and players use a technique known as circular breathing where they inhale through the nose while exhaling through the mouth simultaneously.
Traditionally, didgeridoos were played for ceremonial dancing and singing. Only men were able to play or sing, but both women and men were able to dance. Female didgeridoo players do exist but they play on an informal basis and are not encouraged. The taboo is especially known in the indigenous groups of South East Australia where woman who played or even touched a didgeridoo was considered "cultural theft".
Aren't you glad you aren't indigenous Australian? I know I am!
I have heard them played and have to say that there is no common comparison to any other instrument I have heard before.