Trampoline was not an official Olympic event until the 2000 Sydney Games. The bouncy discipline demands a high level of skill from the athletes, and provides plenty of aerobatic entertainment for the spectators, but is still relatively unknown, so here's a quick tutorial.

Developed in 1934 in the US, trampoline was originally used to train astronauts, and as a training tool and safety net for other sports such as diving, gymnastics and freestyle skiing. It soon became so popular that a new sport was born.

The graceful movements are like ballet in the air. It's enjoyable just to sit and watch. But here are some tips to help you understand the sport more.

In competition, gymnasts perform sets of 10 different combinations while staying in the air as long as possible -- around 20 seconds in total. The first two routines, one compulsory and one optional, decide who gets into the finals, to do a third routine.

Competitors bounce to a height of about 6 meters. They're given scores for skill, difficulty and "time of flight".