How has the hot air balloon changed over time?

Hot air balloons have evolved significantly since their invention in the 18th century. Early designs were made of fabric and paper, relying on open flames for heating, while modern balloons utilize sturdy, heat-resistant materials and propane burners for more controlled and efficient heating. Advancements in technology have improved safety features, navigation systems, and overall performance, enabling longer flights and better maneuverability. Additionally, the aesthetic designs and uses of hot air balloons have diversified, ranging from competitive sports to popular attractions in festivals.