Necessity isn't the only mother of invention. Though it wasn't always easy to get patents or the credit they deserved, women are responsible for many items we use today.
1. THE PAPER BAG
America got a brand new paper bag when cotton mill worker Margaret Knight invented a machine to make them with a flat square bottom in 1868. (Paper bags originally looked more like envelopes.) A man named Charles Annan saw her design and tried to patent the idea first. Knight filed a lawsuit and won the patent fair and square in 1871.
Lightweight, high-tensile Kevlar—five times stronger than steel—will take a bullet for you. DuPont chemist Stephanie Kwolek accidentally invented it while trying to perfect a lighter fiber for car tires and earned a patent in 1966.
3. THE FOOT-PEDAL TRASH CAN
Lillian Gilbreth improved existing inventions with small, but ingenious, tweaks. In the early 1900s, she designed the shelves inside refrigerator doors, made the can opener easier to use, and tidied up cleaning with a foot pedal trash can. Gilbreth is most famous for her pioneering work in efficiency management and ergonomics with her husband, Frank. Two of their 12 children, Frank Jr. and Ernestine Gilbreth, humorously wrote about their home/work collaborations in the book Cheaper by the Dozen.
Elizabeth Magie created The Landlord's Game to spread the economic theory of Georgism—teaching players about the unfairness of land-grabbing, the disadvantages of renting, and the need for a single land value tax on owners. Fun stuff! Magie patented the board game in 1904 and self-published it in 1906. Nearly 30 years later, a man named Charles Darrow rejiggered the board design and message and sold it to Parker Brothers as Monopoly. The company bought Magie's patent for the original game for $500 and no royalties.
5. WINDSHIELD WIPERS
Drivers were skeptical when Mary Anderson invented the first manual windshield wipers in 1903. They thought it was safer to drive with rain and snow obscuring the road than to pull a lever to clear it. (Another woman inventor, Charlotte Bridgwood, invented an automatic version with an electric roller in 1917. It didn't take off, either.) But by the time Anderson's patent expired in 1920, windshield wipers were cleaning up. Cadillac was the first to include them in every car model, and other companies soon followed.
6. DISPOSABLE DIAPERS
Marion Donovan didn't take all the mess out of diaper changing when she patented the waterproof "Boater" in 1951. But she changed parenting—and well, babies—forever. The waterproof diaper cover, originally made with a shower curtain, was first sold at Saks Fifth Avenue. Donovan sold the patent to the Keko Corporation for $1 million and then created an entirely disposable model a few years later. Pampers was born in 1961.
7. THE DISHWASHER
Patented in 1886, the first dishwasher combined high water pressure, a wheel, a boiler, and a wire rack like the ones still used for dish drying. Inventor Josephine Cochrane never used it herself, but it made life easier for her servants.
8. LIQUID PAPER
In the days before the delete key, secretary Bette Nesmith Graham secretly used white tempera paint to cover up her typing errors. She spent years perfecting the formula in her kitchen before patenting Liquid Paper in 1958. Gillette bought her company in 1979 for $47.5 million. And that's no typo.
9. ALPHABET BLOCKS
Children don't read books by anti-suffrage author Adeline D.T. Whitney these days—and that's probably for the better. But the wooden blocks she patented in 1882 still help them learn their ABCs.
10. THE APGAR SCORE
Life is a series of tests, starting with the Apgar, named after obstetrical anesthesiologist Dr. Virginia Apgar. In 1952, she began testing newborns one minute and five minutes after birth to determine if they needed immediate care. About 10 years later, the medical community made a backronym—an acronym designed to fit an existing word—to remember the criteria scored: Appearance, Pulse, Grimace, Activity, and Respiration.
11. MARINE SIGNAL FLARES
Communication between ships was once limited to colored flags, lanterns, and screaming things like "Thar she blows!" really loudly. Martha Coston didn't come up with the idea for signal flares all by herself. She found plans in a notebook that belonged to her late husband. The determined widow spent 10 years working with chemists and pyrotechnics experts to make the idea a reality. But she was only named administratrix in the 1859 patent—Mr. Coston got credited as the inventor.
12. THE CIRCULAR SAW
A weaver named Tabitha Babbitt was the first to suggest that lumber workers use a circular saw instead of the two-man pit saw that only cut when pulled forward. She made a prototype and attached it to her spinning wheel in 1813. Babbitt's Shaker community didn't approve of filing a patent, but they took full advantage of the invention.
13. RETRACTABLE DOG LEASH
New York City dog owner Mary A. Delaney patented the first retractable leading device in 1908. It attached to the collar, keeping pooches under control, while giving them some freedom to roam. Incidentally, someone named R.C. O'Connor patented the first child harness 11 years later. Coincidence? Maybe.
14. SUBMARINE TELESCOPE AND LAMP
It's difficult to find any in-depth information about early inventor Sarah Mather. Her combination telescope and lamp for submarines, patented in 1845, speaks for itself.
15. FOLDING CABINET BED
Sarah E. Goode's folding cabinet bed didn't just maximize space in small homes. In 1885, it made her the first African-American woman with a U.S. patent. The fully functional desk could be used by day and then folded down for a good night's sleep. The Murphy bed came along some 15 years later.
16. THE SOLAR HOUSE
Biophysicist Maria Telkes's place was in the house—the very first 100 percent solar house. In 1947, the Hungarian scientist invented the thermoelectric power generator to provide heat for Dover House, a wedge-shaped structure she conceived with architect Eleanor Raymond. Telkes used Glauber's salt, the sodium salt of sulfuric acid, to store heat in preparation for sunless days. Dover House survived nearly three Massachusetts winters before the system failed.
Apparently, it takes a stain to fight one. In 1952, 3M chemist Patsy Sherman was perplexed when some fluorochemical rubber spilled on a lab assistant's shoe and wouldn't come off. Without changing the color of the shoe, the stain repelled water, oil, and other liquids. Sherman and her co-inventor Samuel Smith called it Scotchgard. And the rest is ... preserving your couch.
18. INVISIBLE GLASS
Katharine Blodgett, General Electric's first female scientist, discovered a way to transfer thin monomolecular coatings to glass and metals in 1935. The result: glass that eliminated glare and distortion, which revolutionized cameras, microscopes, eyeglasses, and more.
Women in computer science have a role model in Grace Hopper. She and Howard Aiken designed Harvard's Mark I computer, a five-ton, room-sized machine in 1944. Hopper invented the compiler that translated written language into computer code and coined the terms "bug" and "debugging" when she had to remove moths from the device. In 1959, Hopper was part of the team that developed COBOL, one of the first modern programming languages.
The wheel is the classic example of early human invention—a quintessential innovation that distinguishes Homo sapiens from all other animals. But in the scope of human history, the wheel is actually a rather young creation. Ancient Mesopotamians in modern-day Iraq became the first people to adopt the wheel only around 5500 years ago, and fairly recent cultures from other parts of the world have managed to make impressive technical accomplishments without wheels at all. (The wheel-less people of Easter Island, for example, transported and erected their towering moai statues less than 1000 years ago.) From booze to the bow and arrow, here are 11 innovations that predate the wheel.
1. BOOZE // 7000 BCE
Some archaeologists are starting to think that the world's first farmers domesticated grains to make beer, not bread. While the extent of alcohol's influence on human civilization is still debated, its antiquity is not. The oldest evidence for booze so far comes from 9000-year-old chemical traces of a fermented cocktail found on a drinking vessel in Jiahu, China.
2. CLOTHING // 150,000 BCE
We're all born naked, but most of us are forced to wear clothes shortly afterwards. Since textiles, leathers, and furs tend to disintegrate over time, scientists have had to get creative in their quest to pinpoint the origin of clothing. The dress above, discovered in Egypt, is at least 5100 years old, but that makes it pretty recent. Clothes actually date back much further: A stone tool from a site in Germany has traces of tanned animal skin, which suggests that humans' Neanderthal cousins were wearing hides 100,000 years ago, and a study from 2011 proposed that the origin of clothes can be traced to the evolution of clothing lice, around 170,000 years ago.
3. JEWELRY // 110,000 BCE
Garments certainly helped humans to compensate for lost body fur and to move into colder climates, but clothes may have also been a cultural invention. As archaeological evidence of jewelry can attest, humans have also been adorning their bodies for decorative purposes for a very long time. Among the oldest surviving pieces of jewelry are 82,000-year-old pierced shells covered in red pigment from a cave in Morocco and a 130,000-year-old eagle-claw necklace found in a Neanderthal cave in Croatia. The above burial, found in Russia at a site called Sunghir, is younger, but still ancient: The man was buried more than 30,000 years ago with an elaborate array of mammoth ivory beads and arm bands, a headband of pierced fox teeth, and a pendant. (Some of the items may once have been sewn onto clothing.)
4. BOATS // 43,000–8000 BCE
Before animal-drawn carts became a preferred mode of transport, there were rafts and boats. The 10,000-year-old Pesse canoe found in the Netherlands is thought to be the world's oldest surviving boat. But humans likely figured out how to navigate the seas for fishing and exploration even earlier. After all, people somehow crossed the seas to populate Australia, Indonesia, and islands in the Pacific at least 45,000 years ago.
5. CALENDARS // 8000 BCE
Long before the gear-wheels of clocks were invented, humans used sophisticated methods to track the passage of time. One group of archaeologists has claimed that the oldest known calendar could be a 10,000-year-old series of 12 pits found in Scotland that appear to mimic the lunar cycle. You can see in the image above how the researchers imagine the system to have worked.
6. GEOGRAPHIC MAPS // 12,000 BCE
Just as they had to invent ways to track time, so, too, did humans have to figure out how to represent space so that they could navigate their world. Archaeologists still debate the meaning of the earliest rock art, but some of the oldest examples of possible prehistoric maps come from Abauntz Cave in Spain. The 14,000-year-old stone tablets are thought to depict mountains, rivers, and ponds, intersected with routes and hunting game-plans. You can see the top and bottom of one tablet above.
7. COOKING // 1.8 MILLION–500,000 BCE
Sometime after humans learned to control fire, they invented cooking. When you start breaking down meat and plants over an open flame, you don't have to expend as much energy chewing and digesting those foods. A conservative estimate for the rise of cooking would be 500,000 years ago, and according to a recent article in Scientific American, some researchers argue that cooking came about 1.8 million years ago by Homo erectus, a direct ancestor of Homo sapiens. They propose that this development in human evolution is what allowed our brain size to increase.
8. MUSICAL INSTRUMENTS // 41,000 BCE
The darkened passageways inside Germany's Hohle Fels cave get even spookier when you imagine the sounds of flutes echoing through the caverns. This is the archaeological site where the world's oldest musical instruments—43,000-year-old bone flutes made of vulture wing and mammoth tusk—have been found. Want to hear what they might have sounded like? One researcher made a replica of the vulture-wing flute, and NPR has the tune.
9. GLUE // 200,000 BCE
The superglue in your toolbox and Elmer's in your kid's classroom have a long pedigree. About 200,000 years ago, Neanderthals roaming Europe used adhesive tar from birch bark to fix their stone spear tips to handles. Recent experiments suggest this type of glue was complex and difficult to make.
10. POTTERY // 18,000 BCE
Thousands of years before the invention of the wheel, people were making vessels for drinking, eating, and storage by pinching, rolling, or coiling clay into shape and baking it until hard. The oldest crude ceramic vessels come from China and date back 20,000 years. The invention of the wheel allowed for the rise of wheel-thrown pottery. Some even argue that the potter's wheel was probably the first type of wheel ever created.
11. BOW AND ARROW // 7000 BCE
The remains of five bows crafted 9000 years ago were found at the Stone Age settlement of Holmegårds Mose in Denmark. But bows and arrows may have been invented far earlier by savvy hunters who wanted an efficient weapon to kill prey from a distance. Some archaeologists have argued that Sibudu Cave in South Africa contains evidence of 64,000-year-old stone-tipped arrows and bows.