In modern times, blimps are almost exclusively used for advertising or novelty purposes. The technology behind the blimp uses some of the same principles as a birthday balloon.
Blimps are filled with lighter than air gases that give them lift. Most modern blimps use helium rather than hydrogen---which, while the lightest of all gases, is also highly flammable.
In 1783, the Montgolfier brothers of Annonay, France, became the first humans to travel by using a gas---hot air, which rises as it gets warmer. Instead of an egg-shaped blimp, the Montgolfier brothers used a large balloon.
The Hindenburg tragedy led to modern blimps abandoning the use of hydrogen. On May 6, 1937, the Hindenburg's hydrogen supply exploded in just 34 seconds after a small fire on board on the craft.
In order to keep a blimp's helium from making it float away, an extremely strong latch attaches to the mast to the blimp. Blimps are strong enough to withstand hurricane-force winds.
One of the most famous blimps, the Goodyear blimp, can travel up to 53 mph; a typical trip lasts about eight hours for a distance of 300 miles.
