Balloons can be divided into two types - hot-air and gas-filled.

The first use hot gas to fill the envelope, creating lift, while the second use a lighter-than-air gas to get airborne. In flight, they have different methods of  using the air currents at various altitudes. At the WAG, the competition is for hot-air types.

These are the modern successors of the balloon flown by the Montgolfier Brothers in 1783, and have no means of propulsion. Competitions consist of precision tasks, where pilots use the winds at different altitudes to navigate towards set goals and targets. Their pilots must therefore exercise particular skills to analyse weather conditions, observe natural features, and make the best use of burning propane gas to control their altitude.

Launches are particularly spectacular, with balloons painting amazing and colourful pictures in the sky. A GPS transmitter reports the position of each balloon allowing a large-screen presentation of the race, regardless of how far away the balloons are.