Answers to all your "burning" questions! (I couldn't resist)
Despite what you may think, hot air balloons are surprisingly badass. If you think about it, its a giant flamethrower that carries people around. The only thing bad about it is the fact that it is a fucking balloon that carries a basket. That you sit in. But then again, it was discovered by the French. To give you an idea of how much of a batshit crazy idea this was originally, condemned criminals were to be the first pilots of the early hot air balloons. Even today, hot air ballooning seems pretty retarded with a 50 pound burner and over 400 pounds of liquid propane surrounding you. All in a straw basket.
The theory behind the hot air balloon is that if you heat the air inside the balloon, the density is lower than the cooler air outside the balloon, and therefor, it will rise. And to ignite the burner, the pilot basically sticks his hand into it and uses a flint spark lighter to ignite the mass of propane that is pouring out of the hole.
Hot air balloons can be made into a variety of hilarious shapes, such as flying cows, bees, condoms or hotdogs. They are made of nylon, with the bottom (closest to the jet) being made of a fire retardant material. This is to try to lessen the chance of you ending up in a burning fireball hurdling towards the ground.
Richard Branson (the owner of Virgin) is surprisingly good at "ballooning". He flew 4767 miles from Japan to northern Canada, and undoubtedly faced horrible atrocities along the way. On this flight, his balloon, the Virgin Pacific Flyer, had reached speeds of nearly 400 fucking kilometers an hour and had set the ground speed record for hot air balloons, probably because nobody else gave too much of a shit about it.