Water Tubing is an individual activity where participants ride an inflatable tube pulled by a motor boat.

Water tubing is a recreational activity performed on an inner tube and generally consists of two types: towed and free-floating, or river tubing. Towed tubing usually takes place on a large body of water and involves tubes being tethered to powered watercrafts and then towed through the water. In free-floating, or river tubing, riders are moved down the river by the natural current.

To use an inflatable inner tube to be either towed by a watercraft, or free-float on a river or lake.

Depending on the particular river or outfitter, rules on the river can vary.

Inner Tube

Law enforcement and tube outfitters warn against or prohibit the use of glass containers on the river to ensure the safety of riders.

Free-Floating - tubing down a river powered by the river's current

Towed Tubing - tubing on a lake or river while being tethered to a powered watercraft

http://en.wikipedia.org/wiki/Tubing_(recreation)#Equipment