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The diagram illustrates a working principle of a hot air balloon.

Overall, a hot air balloon comprises of three components: envelope, burner and basket, which serves different functions. The envelop is clearly a largest part of the whole hot air balloon.

In detail, the envelope is an actual balloon, which is made from gores and panels. Below is some features like skirt and rope, which intergrate the above part with the remaining one. The burner contains the mixed gas (propane and air), producing flame to heat the air. When the hot air denses less than the regular air outside, it rises from the ground. The last component, basket, carries cargo or passengers and two cyclinders containing propane inside, a main fuel used to produce hot air. An other point to note is a parachute valve, which is a self-sealing flap that allows the pilot of the air balloon to control the rate at which the hot air can escape.