what different techniques are used in it?
Landing involves lining up for an approach into wind and, just before touching down, "flaring" the wing to minimise vertical and/or horizontal speed.
Paragliding
Landing involves lining up for an approach into wind and, just before touching down, "flaring" the wing to minimise vertical and/or horizontal speed. 
how long do gliders stay in the air Glider pilots can stay airborne for hours by flying through air that is ascending as fast or faster than the glider itself is descending, thus gaining potential energy. is it a sport? Yes, a competitive air sport. how is it done? Pilots fly unpowered aircraft known as gliders or sailplanes using naturally occurring currents of rising air in the atmosphere to remain airborne. does it face any challenges? UNANSWERABLE are there any competitions of it held? Local and national competitions along with biennial World Championships. what is the championship mentioned about? It is a gliding competition held every two years or so. who organizes it? The FAI Gliding Commission. when was it founded? The Commission was founded in 1932. does it present any awards? The Commission makes awards for great achievements and meritorious service. Eg- The Lilienthal Medal. are there any other sports related to it? Yes, hang gliding and paragliding. what does the latter mean? It is the recreational and competitive adventure sport of flying paragliders.
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Paragliding [SEP] Techniques
Landing involves lining up for an approach into wind and, just before touching down, "flaring" the wing to minimise vertical and/or horizontal speed. This consists of gently going from 0% brake at around two metres to 100% brake when touching down on the ground. During the approach descent, at around four metres before touching ground, some momentary braking (50% for around two seconds) can be applied then released, thus using forward pendular momentum to gain speed for flaring more effectively and approaching the ground with minimal vertical speed. In light winds, some minor running is common. In moderate to medium headwinds, the landings can be without forward speed, or even going backwards with respect to the ground in strong winds.