Gliders are light aircraft which achieve unpowered flight not only gliding through the air but by climbing using the rising air masses, the most common of which being the thermal. The designs are improving all the time and they have even taken a step beyond pure gliders. There are gliders with optional engines, which can be used to sustain flight or just launch the glider.
The normal launch methods are to either be towed behind a powered aircraft using a 60m rope and be released once airborne or to use a winch with a powerful stationary engine to rapidly wind in 1000m of wire cable attached to the glider.
The FAI which is the international governing body for the many airsports including gliding has defined quite a number of class for gliders. These include a two seater and world class which is a specific low cost and easy to assemble glider.
These names actually include all light weight slow flying aircraft. They come in all shapes and sizes and include powered parachutes, powered paragliders, balloons, basic helicopters, hang glider style wings as well as the more traditional looking lightweight planes. It is all the more confusing in that the names and classifications vary in different countries. This is also the case for safety regulations which are very strict in the UK, Germany and Italy yet almost non existant in France and the US which requires no training or license for some of the classes.
Since it began in the seventies this type of flying has grown rapidly and in affluent countries it accounts for 20% of the civil air traffic. There are now many sophisticated light weight aircraft on the market which are actually considered as high performance aircraft. These look like small aeroplanes and the common name for this group is recreational aircraft