Hot air balloons can be used for short distance travel only. Since hot air balloons travel at the speed of the wind, it is an extremely slow way to travel, and not entirely reliable since the wind can blow you off course quickly. Hot air balloons have been used for many different things, since their invention.
They have been used to signal military movements in China. They were used during some of the early wars in the United States for observation of enemy movements as well. The primary purpose of the hot air balloon is for enjoyment. There are festivals several places around the world each year, where thousands of hot air balloons are in the air.
There are also places where one can go and be taken up in a hot air balloon for a short ride. All those who are operating hot air balloons are required to have the necessary licenses, such as a pilot's license. Even though the aircraft does not travel at high speeds, it is still regulated.