Original links are included though some may have expired.

The Numbers:

First airplane flight: December 17, 1903

What They Mean:

The airplane is 100 years old today. But claims for man-powered flight in blimps, gliders, and flying suits go back centuries. Under Ottoman Sultan Murat IV (1623-1640), for example, a man named Hezarfen Celebi supposedly jumped off the Galata Tower in Istanbul wearing an artificial wing, and sailed safely over the Bosporus. Glider flight, pioneered by Yorkshire engineer Sir George Cayley, dates to 1853. The truly reliable first date for manned flight, though, is November 12, 1783, when two French aristocrats rode a hot-air balloon built by Etienne and Joseph Montgolfier half a mile into the air. Balloon flight was common in the 19th century, mainly for sightseeing but also for more practical uses (defenders of Paris launched 65 manned communications balloons during the Franco-Prussian War in 1870) and led to the invention of steerable blimps by 1884.

The Wright Brothers, of course, turned all these things into curiosities. A century after their first flight, the International Air Transport Association counts 10,237 big civil airplanes, operated by 189 commercial airlines, flying worldwide. (Including helicopters and small planes, the United States has nearly 225,000 planes.) Each year these planes handle 29 million tons of cargo and 1.6 billion passengers, and travel 2 billion miles. Air cargo is light compared to sea and land freight -- U.S. seaports handle 1.1 billion tons of cargo a year -- but its value is high, since planes typically carry perishable or high-priority goods. Examples include the 110 million fresh-cut Colombian roses flown in each February for Valentine's Day, the 25,000 kilos of live Maine lobster flown out monthly to Japan; and 232 million pounds of priority international mail annually carried in and out of the United States.

Undersea travel is less publicized, possibly less romantic, but just as impressive a technical achievement. The first recorded submarine journey took place in London in 1620, just before Celebi's alleged jump, in a submersible wooden boat covered with oiled leather. Built by Dutch inventor Cornelius Drebbel for King James I, it seems to have traveled just under the surface for about two miles down the Thames. Some 19th-century attempts to develop submarines also ended as partial successes but long-term dead ends. France's 140-foot, 420-ton Plunger, like Drebbel's boat, was wisely abandoned after a trial dive in 1860; three years later, the infamous Confederate Civil War submarine Hunley sank on all three of its dives, though it took a Union ship down with it on the last one. The inventor of the first practical sub was John Holland of Patterson, New Jersey, who tested a small gas-powered model in 1878 and built the U.S. Navy's first seaworthy submarine in 1900. But even after 125 years, submarine travel still awaits its commercial takeoff -- almost all of the world's 600 subs are military (as compared to only 6,000 of the United States' 225,000 planes) though some small ones are used for science, underwater exploration, and tourism around famous shipwrecks and coral reefs.

Further Reading:

More about airplanes: Some other airplane pioneers -- Brazil's Alberto Santos-Dumont built and flew Latin America's first airplane in 1906. He also steered a blimp around the Eiffel Tower in 1901. Asia's first plane was built and flown (in Oakland, California) in 1909 by 21-year-old Yanping native Feng Ru; the second by Sanji Nagahara in 1911. New Zealand farmer Richard Pearse patented a plane in 1906 and may have flown it a year earlier. NASA's Centennial of Flight page:
http://www.centennialofflight.gov/hof/index.htm

More about tower jumping: Sultan Murat IV seems to have hated the idea of flight and exiled Celebi to Algeria. Murat also hated coffee-drinkers, unexpected noises, tobacco pipes, and poorly maintained roads. He liked executions, though. A brief recap of Celebi and his artificial wing from the Istanbul Metropolitan Authority:
http://www.ibb.gov.tr/istanbuleng/25003/sutunkule.htm;
and a hair-raising biography of Murat:
http://www.xs4all.nl/~kvenjb/madmonarchs/
murad4/murad4_bio.htm

Earlier and mistier tower-jumping claims are made for two 9th-century Cordovan physicians named Armen Firman and ibn Firnas -- respectively using a parachute and a primitive glider -- and an 11th-century Anglo-Saxon monk named Elmer. Firman seems to have escaped with only minor injuries. Chinese Emperor Kao Yang (Qi Dynasty, reigned in modern Henan from 550-559 AD) is supposed to have experimented in this vein too, by throwing criminals off a tall platform called the "Terrace of the Golden Phoenix" with bamboo-mat 'wings' strapped to their shoulders.

More about balloons: Pilatre de Rozier, one of the first two balloon 'aeronauts,' was killed in 1785 when another balloon exploded at the start of a planned trip over the English Channel:
http://www.2002worldsballoons.com/
uk/frames.php?centre=montgolfiere/
histoire&ssmenu=montgolfiere/ssmenu

The world's oldest aerial photograph (of downtown Boston in 1860), taken by James Wallace Black:
http://pollux.geog.ucsb.edu/~jeff/115a/history/
firstairphoto_boston.jpg

More about submarines: The history of the submarine, from the U.S. Navy Office of Submarine Warfare:
http://www.chinfo.navy.mil/navpalib/cno/n87/n77.html

The Hunley Association:
http://www.hunley.org/

And lastly: Theodore Roosevelt seems to have been the first person to travel both in the sky and under water. A few months after his 1905 Inauguration ceremony, Roosevelt dove into Long Island Sound on the Navy's second commissioned submarine. In 1910, after leaving office, he took a four-minute plane flight while visiting St. Louis. The Theodore Roosevelt Association:
http://www.theodoreroosevelt.org/