Water skiing is a sport and recreational activity invented in Lake City, Minnesota in 1922 and is popular in many countries around the world where appropriate conditions exist - an expanse of water unaffected by wave motion. Rivers, lakes, and sheltered bays are all popular for water skiing.
Standard water skis, originally made of wood but now usually constructed out of fibreglass-based composites, are of similar length to downhill snow skis but are somewhat wider. Instead of a rigid binding, they have rubber mouldings in which the feet are placed. Skiers are pulled along by a rope with a handle fitted at one end and attached to a powerboat at the other.
Recreational skiers usually learn to ski with a ski on each foot, but as they improve usually progress to using a single ski, placing the other foot into another binding behind the main one. Beginners on two skis are usually pulled along at around 25-35 kilometres per hour, whereas more advanced social skiers travel at between 40 and 55 kilometres per hour - once confidence is gained it is actually easier to travel faster than at slower speeds because of the greater lift and stability.
Within the confines of being pulled along by the boat, skiers can control their direction by balancing their weight on different sides of their ski. This is used to zip back and forth behind the boat.
There are several forms of competition performed on waterskis. Slalom most resembles recreational water skiing. In it, a set of buoys are set up. The boat drives through the middle of the buoys, and the skiier must pass to the outside of each buoy. The winner of the contest is the individual who can complete going round the buoys with the shortest rope. Elite skiers can perform this feat with a rope shorter than the distance between the boat center (the origin of the rope) and each buoy!
Trick skiing is performed using two very short skis rather than the conventional gear. In it, skiiers try to perform tricks somewhat similar to those of gymnasts while being pulled along by the boat. Trick skiing is judged by the difficulty of the tricks performed and the accuracy of execution.
The ski jump is performed on two long skis similar to those a beginner uses (but with no tail fin). Skiers towed behind a boat at fixed speed manoever to achieve maximum speed when hitting a ramp floating in the water, launching themselves into the air with the goal of travelling as far as possible before touching the water. Good ski jumpers can travel up to 60 metres.
Ski races simply involve a powerboat race with a skier attached. These events are usually conducted on rivers to make the course more interesting. One such event held at Echuca on the Murray River, Australia is the Southern 80. Skiers and boats typically average 160 km/h over the 80 kilometre course.
A variation of the sport, barefoot skiing, as the name suggests involves water skiing without the aid of skis.