(FORTUNE Magazine) – Play

1958 / Legos The plastic Lego block was introduced in 1949, and since then slightly more than 203 billion have been made. It seems safe to assume that at least ten billion are under sofa cushions, three billion are inside vacuum cleaners, and right now a barefoot parent has just stepped on one. Legos got their start as Automatic Binding Bricks, invented by Ole Kirk Christiansen, a master carpenter in Billund, Denmark. The first ones looked much like today's, with a key difference: The stud-and-coupling system that allows kids to snap the bricks together wasn't introduced until 1958. There are now 2,000 different Lego elements, and Lego theme parks in the U.S., Britain, and Denmark.

1900 / Kodak Brownie camera 1935 / Kodachrome film 1948 / Polaroid 1976 / JVC videorecorder 1982 / Philips/Sony CD

Work

1900 / Paper clip Oh, sure, the technological revolution of the past 20 years has wrought some amazing changes in the workplace. Now, instead of spending half an hour typing a letter, it is possible to waste half an hour cursing a broken printer. But when it comes to epic changes in office life, consider the lowly paper clip. Before Norwegian Johan Vaaler devised a bent metal clip in 1900, papers were secured by straight pins, which had the predictable effect of gouging their recipients. Vaaler, alas, didn't realize the import of what he had done and sold his patent to a stationer. Gem Manufacturing of Britain soon introduced its own version, a design still widely used today.

1959 / Xerox photocopier 1966 / Xerox fax machine 1971 / Intel microprocessor 1980 / 3M Post-it Notes 1984 / Apple Macintosh

Travel

1936 / DC-3 To answer the obvious question: Yes, there was a DC-1 and a DC-2. Donald Douglas built the DC-1 in 1933 to fill an order from TWA, which wanted a passenger plane similar to the recently launched Boeing 247. Douglas introduced the slightly improved DC-2 a year later, but it was the DC-3 that revolutionized air travel. Built for American Airlines, it flew across the country in record time--17 hours and 30 minutes, six hours faster than the DC-2. The decreased flight time led to a 500% rise in air travel between 1936 and the start of World War II. Douglas' planes were then drafted into service to ferry troops and armaments around Europe. The company eventually produced more than 10,000 military and commercial versions of the DC-3.

1903 / Harley-Davidson motorcycle 1908 / Ford Model T 1950s / Skateboard 1957 / Boeing 707

Home

1907 / Vacuum cleaner Remember that scene from 20,000 Leagues Under the Sea in which the Nautilus is menaced by a giant squid? The first vacuum cleaners worked something like that. They were mounted on wagons outside of houses, and rubber hoses snaked inside to suction dirt from carpets, draperies, and davenports. Homeowners, not surprisingly, found this inconvenient, creating a demand for the product invented in 1907 by James Murray Spangler: the smaller, less intimidating in-home vacuum cleaner. After trying to sell his invention on his own, Spangler joined with William Hoover, and Hoover Co. was born. An enduring mystery: why the upright vacuum cleaner is known as the Hoover rather than the Spangler.

1918 / Frigidaire refrigerator 1928 / Home air conditioner 1942 / Permacel duct tape 1946 / Tupperware 1967 / Amana microwave oven

Communications

1935 / The paperback book Yes, yes, Gutenberg made a very nice Bible. But could you slip it into your pocket and read it on the subway? It was Allen Lane, managing director of the British publishing house Bodley Head, who came up with the paperback book. According to company lore, Lane was returning from a weekend vacation with Agatha Christie and her husband when he scanned the newsstand for something to read. Finding only magazines and reprints of Victorian novels, Lane hit upon the idea of the portable book. The first ten paperbacks--appearing under the brand name Penguin--were introduced July 30, 1935; they included works by Christie and Ernest Hemingway.

1921 / RCA radio 1939 / RCA television 1991 / World Wide Web

Clothing

1939 / Nylons Silkworms had nothing on Wallace Hume Carothers. Silk stockings were prone to run, tear, or "pop," but stockings made with Carothers' synthetic nylon were both sheerer and tougher than their organic counterparts. Even though nylons initially cost twice as much as silk stockings, women lined up to buy them when they were introduced on May 15, 1940. By the end of the year customers had bought anywhere from 35 million to 64 million pairs, depending on which numbers you look at. Carothers, alas, didn't live to see his product swathe the legs of American women; a manic depressive plagued by self-doubt, he took cyanide in 1937.

1913 / Zipper 1914 / Bra 1936 / Bass penny loafer 1954 / Velcro 1959 / Lycra 1961 / P&G Pampers

Health and Grooming

1903 / Safety razors When King Camp Gillette was working at the Crown Cork company, a mentor offered him some friendly advice: "Why don't you try to invent something like [a cork], which, when used once, is thrown away, and the customer comes back for more?" While shaving one day in 1895, Gillette realized there might be a market for a razor with a disposable blade. It took him eight years to develop the blade and start production, but then the product took off. During World War I, Gillette supplied 3.5 million razors and 36 million blades to U.S. soldiers, creating a base of customers who kept coming back for refills long after the Treaty of Versailles.

1921 / Johnson & Johnson Band-Aid 1928 / Penicillin 1931 / Tampax tampon 1960 / Searle birth control pill 1988 / Eli Lilly Prozac