The Fascinating Origins of 20 Revolutionary Inventions That Transformed the World

It’s hard to picture life without smartphones or to recall a time when Wi-Fi wasn’t ubiquitous, but many of today’s essential technologies owe their existence to groundbreaking inventions from the past. While we often take everyday marvels—such as toilets, seat belts, and suspension bridges—for granted, it’s just as easy to forget how unexpected inventions like the Super Soaker or the pizza saver have reshaped our world. From blood banks to barcodes, here are the captivating stories behind 20 inventions that changed the course of history.

1. Suspension Bridges

Suspension bridges have ancient origins, with one in China still standing that once utilized bamboo and dates back at least 1000 years, possibly over 2000. However, the suspension bridges that emerged in the 1800s marked a significant advancement: They were more affordable to build, simpler to maintain, and designed to handle flooding more effectively. Over time, these bridges enabled crossings over much larger bodies of water, withstanding fierce storms and the growing weight of foot and vehicle traffic in urban areas, all while greatly reducing travel time. In the mid-1800s, engineer John A. Roebling observed that the Allegheny Portage Railroad used fragile hemp ropes, which inspired him to invent a method for spinning and manufacturing wire rope, a technology he later applied to suspension bridges. This allowed the wire to be spun and secured on site, speeding up the construction process.

Roebling's breakthroughs led to his designs for the Niagara River Gorge Bridge, the Sixth Street Bridge in Pittsburgh, and the legendary Brooklyn Bridge during the second half of the 19th century. Although the Brooklyn Bridge followed John Roebling's original design, his son, Washington, took over as chief engineer after his father's death in 1869. When Washington fell ill with decompression sickness (or 'the bends'), his wife, Emily, stepped in and assumed many of his responsibilities. In an era when women were excluded from STEM fields, Emily studied cable construction, stress analysis, and other suspension bridge engineering principles, playing an essential role in the completion of the project.

Today, suspension bridges are found across the world, making it possible for people to safely and efficiently cross vast gaps and bodies of water. These bridges have expanded beyond simple river crossings—Japan’s Akashi Kaikyo Bridge, for example, spans 12,828 feet across the Akashi Strait, with a central span measuring 6527 feet in length.

2. Toilets

Dry and flush toilets have been a part of human life for millennia, and while many of us take them for granted today, life would undoubtedly be much more difficult and unpleasant without them. Kimberly Worsham, a sanitation expert and founder of FLUSH (Facilitated Learning for Universal Sanitation and Hygiene), tells Mytour, “Toilets are the key to a thriving, healthy society.” A dedicated place for human waste has been crucial in reducing outbreaks of diseases like cholera and typhoid, which were widespread in cities before the advent of flush toilets, indoor plumbing, and sewer systems. For dry toilets, the waste collected can be processed and repurposed for agricultural use.

Many trace the modern flush toilet back to John Harington, the godson of Queen Elizabeth I, but flush toilets existed long before his time. In fact, one in Knossos, dating back to the 16th century BCE, was even linked to a sewer system. “Flush toilets like his had been used in Western Europe during the Roman Empire, but after Rome's fall, Europe returned to outdoor sanitation practices,” says Worsham. “Those systems fell into disrepair.” Meanwhile, places like East Asia and parts of the Middle East continued to use toilets, even as Europe regressed.

During the time Harington was innovating, the common options were chamber pots, garderobes—“dreadful closets with holes in the ground”—or simply going outdoors. Harington sought to bring toilets back indoors and make the bathroom experience more comfortable. However, his design was far from perfect: Rather than connecting to a sewer, it featured a pipe that emptied into a lower chamber, requiring periodic emptying. Worse still, the toxic and flammable gases produced by decaying waste could flow back up the pipe, creating hazardous conditions. As a result, Harington's invention didn't catch on, and he only built a few prototypes.

In 1775, Scottish watchmaker Alexander Cumming developed the revolutionary S-trap, a plumbing device attached to the back of the toilet. “This was groundbreaking because it used water in the trap to block harmful gases from entering the home, and kept waste from flowing back into the toilet,” says Worsham. “Once Cumming patented his design, it was like the beginning of a flush toilet renaissance.” The toilet industry then saw significant innovation, with figures like Thomas Crapper (who, according to Worsham, “created a killer marketing campaign for toilets”) making their mark. As materials for toilets became more affordable, they became widespread, improving sanitation and safety. “We saw mortality rates drop,” Worsham says, “and our living spaces became much cleaner—literally.” Waste that went into flush toilets was directed to sewers or septic systems, keeping it out of streets and drinking water.

However, there is still much work to be done to ensure that everyone has access to toilets. Worsham notes, “1 in 4 people globally lack access to basic toilets, and 1 in 2 don't have access to safely managed toilets—those that ensure waste is never returned untreated to the environment.” Without proper sanitation, people are sicker, miss more work and school, and fall into cycles of poverty and inequality. Fortunately, efforts to improve sanitation continue: “There have been impressive projects by social enterprises and NGOs in various parts of the world, developing newer, more eco-friendly toilets,” says Worsham. “Innovations also integrate fecal waste with organic matter—like food scraps—to create valuable agricultural products such as fertilizer and animal feed. We're moving towards circular economies, and it's very exciting.”

3. The Walkman

Although many young people today first encountered a Walkman when they saw Chris Pratt’s Peter Quill rocking one in 2014’s Guardians of the Galaxy, they unknowingly honor the device each time they play a song on their smartphones. Transistor radios existed since the 1950s, but it was Sony co-founder Masaru Ibuka who truly transformed the concept of listening to music wherever and whenever you wanted (as long as you had a cassette tape). Ibuka’s main motivation was to create a portable music player for his flights. The Sony Walkman debuted in Japan in 1979 (and in the U.S. in 1980), quickly becoming the iconic accessory of the '80s. Compact, lightweight, and portable, the Walkman and its headphones became symbols of convenience. Over the years, devices like Sony’s Discman, Apple’s iPod, smartphones, and today’s Bluetooth headphones have kept the focus on portability and ease of use.

4. The Pill

By the close of the 19th century, bicycles became a relatively affordable and convenient way for women to gain a sense of independence. The freedom to move, along with the clothing they wore, was less restricted than ever before. Decades later, another groundbreaking item would arrive, further transforming women's rights: the Pill.

Hormonal birth control pills (commonly referred to as the Pill) weren't the first oral contraceptive; people had long relied on various concoctions, such as mercury or toxic pennyroyal. By the early 1900s, there was growing momentum in the U.S. for better contraceptives—Margaret Sanger opened the nation's first birth control clinic in 1916, though it was raided and shut down. Work on the contraceptive pill itself didn't begin until the 1950s, when biologist Gregory Goodwin Pincus and gynecologist John Rock, with support from Sanger and philanthropist Katharine McCormick, teamed up to develop a “magic pill” that could prevent pregnancy. “I would argue that effective contraception was probably the most significant change for women in the 20th century,” said Linda Gordon, author of Woman's Body, Woman's Right: A Social History of Birth Control in America, in an interview with Allure.

When the Pill was first released in 1957, it was approved only for regulating menstruation [PDF]. Even after the FDA approved it for contraceptive use in 1960, it wasn't immediately accessible. In some U.S. states, unmarried women were prohibited from purchasing the Pill until 1972. Over time, oral contraceptives evolved, with a variety of brands now available on the market, offering monophasic, biphasic, and triphasic options that vary in the levels of estrogen and progestin.

The creation of the Pill did more than just give women control over their sexual health and fertility—it empowered them to delay marriage, pursue further education, and progress in their careers. As Vanessa Grigoriadis wrote in New York magazine, “These days, women’s twenties are as free and fabulous as they can be, a time of boundless freedom and experimentation, of easily trying on and discarding identities, careers, partners. The Pill, the most popular form of contraception in the U.S., remains the symbol of that freedom.”

5. Super Soaker

For years, squirt guns were flimsy plastic toys, barely powerful enough to water a plant. But when the first Super Soaker—initially known as the Power Drencher—was released in 1990, it brought an aura of Schwarzenegger-like machismo with it. Featuring a sophisticated air-pressure system, it could drench unsuspecting victims from a distance far greater than any previous water guns. The appeal of creating chaos at family gatherings and school events was simply too much for kids to resist, leading to over 2 million units flying off the shelves in its first year. Al Davis, the former EVP of Larami, wrote in his book Super Soaker that “The deliveries would come into the stores, and the clerks wouldn’t even have time to put them on the shelves. They’d just take them out of the boxes and sell them to the kids waiting in line for them.”

In the first quarter-century since its release, over 175 different versions of the Super Soaker were introduced, racking up more than $1 billion in sales. In 1995, Hasbro acquired Larami and the Super Soaker brand, and ever since, the company has continued to roll out larger models that promise even more water-splashing mayhem each summer.

When the Strong National Museum of Play inducted the Super Soaker into its National Toy Hall of Fame in 2015, former Curator Patricia Hogan remarked, “[The] Super Soaker revolutionized neighborhood play. The small squirt guns of the past required close-range action, but Johnson’s invention could drench from a distance, forcing opponents to either retreat quickly or engage in a chase. This new style of play required kids to sprint, calculate target distances, and think about the physics of velocity and arc. Strategizing and analyzing the best approaches to victory became a key part of the fun. And if kids got drenched in the process? It was all just clean, fun entertainment.”

None of this would have been possible without the unconventional thinking of former NASA engineer Lonnie Johnson. The idea for the Super Soaker came to him in the early 1980s, while he was testing a heat pump he had developed that used water as a coolant. While the pump worked well, he also realized how enjoyable it was to shoot powerful jets of water from it across his bathroom.

“I had difficulty getting people to grasp the harder science behind my inventions like the heat pump or digital measuring instrument,” Johnson told Forbes. “But I thought a toy would be something everyone could understand and appreciate.”

Although Johnson holds more than 100 patents and contributed to NASA’s Galileo mission to Jupiter, it’s his transformation of the water gun—evolving from a 29-cent novelty item to a summer must-have—that will forever be remembered by generations of kids (and some unsuspecting bystanders).

6. The Blood Bank

Nearly a century ago, patients in need of blood transfusions were in a race against time. Without an organized system for blood donations and with blood preservation methods still in their infancy, there was no way to store it for future use. Patients had to find their own blood donors before it was too late.

In 1937, physician Bernard Fantus pioneered a method to preserve blood for up to 10 days and established the country’s first “blood bank” at Chicago’s Cook County Hospital. This allowed people to “deposit” their own blood for personal use or to be donated to others with compatible blood types.

Around the same time, surgeon Charles R. Drew developed a method for separating plasma from whole blood, discovering that blood transfusions could be successfully carried out using just plasma alone when whole blood wasn’t necessary. Plasma could be dried for long-term storage in blood banks. As World War II ravaged Europe, Drew partnered with the American Red Cross to create a groundbreaking plasma collection program in the U.S., sending plasma to Britain and effectively establishing a national blood donation system. Drew also worked with the Red Cross to set up “bloodmobiles”—mobile blood donation units that made blood bank operations more sustainable. Today, around 13.6 million units of whole blood and red blood cells are collected in the U.S. annually, saving countless lives.

7. Space Telescopes

In the 1940s, when Lyman Spitzer proposed the idea of creating a space telescope, humanity could only observe the universe through ground-based instruments. Earth's atmosphere acted like a curtain, distorting images and preventing the detection of distant celestial objects. Spitzer’s work laid the foundation for the Hubble Space Telescope, the first major space-based optical telescope, which was launched in 1990 and named after American astronomer Edwin P. Hubble.

Over its 30-year mission, the Hubble has helped determine the universe’s age (13.8 billion years), accurately measured the distance to a neighboring galaxy, discovered many moons and exoplanets, and captured breathtaking images of space. As art critic Jonathan Jones wrote in The Guardian, 'The Hubble space telescope has brought about a visual revolution, more significant than any recent work of art in transforming the way we see ourselves and the cosmos.' This year, NASA is set to launch the James Webb Space Telescope, the largest and most technologically advanced space telescope ever constructed, to uncover even more secrets of the cosmos.

8. The Pizza Box and Pizza Table

The pizza industry has seen many innovations over the years, but the box that holds your pizza has remained relatively unchanged. In the early 1960s, Tom Monaghan, the founder of Domino's Pizza, worked with Triad Containers in Detroit to design the modern pizza box. Before that, pizzas were delivered in flimsy bags or paperboard bakery boxes that often crumpled under the heat of the pizza. Domino’s introduced corrugated cardboard boxes that were not only durable but also withstood grease and kept the pizzas warm, allowing steam to escape through ventilation holes. The real breakthrough was that these sturdy boxes were stackable, making large-scale deliveries possible.

However, there was one flaw in the design: the top of the box would sometimes collapse and stick to the pizza. The solution to this problem came in the form of the pizza saver, a small plastic device patented by Carmela Vitale in 1985. Shaped like a miniature table, it kept the box lid from touching the pizza, preserving the cheese and toppings during delivery. Vitale, a city council member rather than a pizza business owner, came up with the idea after noticing the issue and inventing a clever fix after years of eating pizza.

9. X-Rays

On a crisp fall evening in 1895, German physicist Wilhelm Röntgen was conducting experiments with electricity passing through low-pressure gases when he made an unexpected discovery. He found a mysterious ray that made a chemically-coated screen glow from a distance. Intrigued, he placed objects between the tube and the screen to observe the shadows they cast. When he tested it with a block of lead, he saw not only the shadow of the lead but also the outline of the bones in his own hand. Further trials revealed that a photographic plate could replace the screen—and thus, the X-ray was born.

Röntgen named his discovery X-strahlen, with strahlen meaning ‘beam’ or ‘ray’ in German, and X symbolizing the unknown quantity, a mathematical convention. His groundbreaking work revolutionized the medical field, allowing for non-invasive detection of diseases and injuries, from detecting broken bones to diagnosing breast cancer. Today, X-rays are also crucial for identifying cracks in structures like aircraft wings and nuclear reactors, making the world a safer place. As radiologist Richard Gunderman wrote in The Conversation, 'Thanks to [Röntgen's] invisible light, we now operate with a much deeper understanding of the universe we inhabit, the molecules and cells of which we are composed, and the diseases that threaten our lives.'

10. Wildlife Cams

The first wildlife cameras were created by George Shiras, a photography-loving Pennsylvania Congressman, around the turn of the 20th century. Inspired by the Ojibwa tribe’s hunting technique called jacklighting, where a fire is placed in the front of a canoe to attract animals, Shiras adapted the idea for photography. In this method, the glowing fire would catch the attention of an animal, causing it to freeze in place, its eyes reflecting the flames. Shiras replaced the fire with a kerosene lamp and the rifle trigger with a camera’s shutter release. Eventually, he upgraded to cameras equipped with flash and triggered by a string.

Today, wildlife cameras have become so lightweight that they can be strapped to marine animals, are powered by batteries allowing them to be left in the wild for months, and have even been attached to robots for safer encounters with dangerous creatures. These advancements have given us an unparalleled glimpse into the lives of animals and their habitats, leading to numerous scientific discoveries. Thanks to wildlife cameras, we now know that fishers are breeding in Washington state for the first time in decades, the critically endangered hairy-nosed otter has returned to Malaysia, and the elusive Siamese crocodile continues to prowl the waters of Thailand. Cameras have also captured footage of previously unknown species, like Tanzania’s grey-faced sengi, an elephant shrew. In 2020, trail cameras were vital for scientists to continue their fieldwork and gather data remotely during COVID-19 lockdowns and travel restrictions.

11. Duct Tape

Duct tape was invented by Vesta Stoudt, an Illinois mother whose sons served in the Navy. Stoudt worked at the Green River Ordnance Plant packing and inspecting ammunition boxes. These boxes were sealed with paper tape that had a wax coating and a tab for opening. Stoudt noticed that the tape was too weak and the tabs often ripped off, making it hard for soldiers to quickly open the boxes during combat. She had an idea: create a waterproof cloth tape to seal the boxes. After being ignored by her supervisors, she took her proposal directly to President Franklin Delano Roosevelt. 'I suggested we use a strong cloth tape to close seams, and make tab of same,' she wrote. 'It worked fine, I showed it to different government inspectors they said it was all right, but I could never get them to change tape.'

The president forwarded her letter to the War Production Board, and her idea was approved. The rest is history. Duct tape has become the go-to solution for everyone, from everyday people to physicists (who use it on particle accelerators) to astronauts (duct tape was used for repairs on the moon). When the Apollo 13 crew had to transfer to the lunar module, duct tape was instrumental in their survival. The module was designed for two people for 36 hours, but after the emergency, it had to accommodate three people for over 86 hours. The crew used duct tape, along with cardboard, plastic bags, and space suit components, to adapt their square carbon dioxide filters to the round holes of the module. Jerry Woodfill, a NASA engineer who helped the crew from the ground, later said, 'Of course … the solution to every conceivable knotty problem has got to be duct tape! And so it was.'

12. Barcodes

On June 26, 1974, a cashier at Marsh Supermarket in Troy, Ohio, scanned a pack of Wrigley’s Juicy Fruit chewing gum, and the scanner automatically recorded the item and its price. This was the first time a barcode was used for a purchase.

The pioneers of this revolutionary system were N. Joseph Woodland and Bernard Silver, who envisioned a way to use lines to encode product information, which could be read by an optical scanner. The idea was born when Silver, a graduate student at Drexel, overheard a conversation between the president of a local supermarket chain and the dean, discussing the need for an automated method of tracking products. Although the dean showed no interest, Silver brought the idea to his colleague Woodland, who believed in its potential so strongly that he left his job and moved to Florida to focus on it. Woodland created the system based on his experience with Morse code (from his Boy Scout days) and sound technology from 1920s cinema. The system was later refined with help from IBM's George Laurer, forming the foundation of modern checkout technology.

Today’s barcodes, known as Universal Product Codes (UPC-A), consist of 12 digits. The first digit indicates the category of the product—‘3’ refers to health-related items—while the other digits identify the manufacturer and specific product. More recent QR codes, which are frequently used by smartphones, provide immediate access to information. Barcodes are widely used across industries, increasing productivity by eight to ten times compared to manual data entry. While they speed up transactions, sometimes they’re not as quick: At Aldi stores, employees memorize popular product barcodes to avoid removing heavy items from carts during checkout.

13. Seat Belts

The idea of using seat belts for safety in transportation was not solely conceived by Nils Bohlin, the Swedish engineer who designed the iconic three-point shoulder and lap belt for automobiles in 1958. Pioneers like the 19th-century aviator George Cayley had already recognized the necessity of keeping individuals secure in moving vehicles like planes. However, it was Bohlin, a Volvo engineer, who sought to enhance the existing two-point lap belts, which at high speeds could cause internal injuries and often offered little protection. His innovative three-point belt stabilized the torso with a shoulder strap, keeping drivers and passengers firmly in place while avoiding the discomfort of the four-point belts worn by pilots or the previous Y-shaped belts placed over the stomach. In a remarkable gesture of corporate generosity, Volvo made the patent for the belt available to other car manufacturers. By the time of Bohlin's passing in 2002, it was estimated that his life-saving invention had saved over a million lives.

14. The Microwave

During World War II, engineer Percy Spencer contributed to the U.S. war effort through his work on magnetrons—tubes that generate electromagnetic waves for radar—while working at Raytheon. His involvement didn’t end with the war. In 1945, while fiddling with magnetrons, Spencer discovered that the peanut cluster candy bar in his pocket had melted into a “gooey, sticky mess.” It didn’t take long for him to realize that the microwaves from the magnetron were responsible, inspiring him to invent a microwave oven that would allow people to heat food in a more controlled manner. The refrigerator-sized 'Radarange' was introduced in the mid-1940s, originally intended for use in restaurants and airplanes, not homes. At $1250—around $17,000 in today’s money—it was too expensive for the average household to adopt.

Over time, designs improved and costs decreased. By 1967, the Radarange had become popular among homemakers. By the mid-1970s, the microwave oven—eventually shortened to 'the microwave'—was becoming a staple in U.S. kitchens, not just for reheating leftovers. Manufacturers marketed the appliance as a quicker, easier, and cooler alternative to traditional ovens. 'Make the greatest cooking discovery since fire,' actress Barbara Hale declared in a 1972 Radarange ad—a line that Don Draper from Mad Men surely would have envied. A 1971 advertisement for General Electric’s Just-A-Minute oven highlighted how its special timer, controls, and recipe booklet removed much of the guesswork from cooking, a welcome relief for nervous cooks everywhere. This gave rise to a wave of cookbooks, like Madame Benoit’s Microwave Cook Book and Barbara Kafka’s The Microwave Gourmet, featuring everything from duck à l’orange to 'Elegant Beef Dinner.' One 1978 cookbook even suggested preparing pie in the microwave (to address the lack of browning, yellow food coloring was recommended). In 1986, Swanson introduced plastic, microwave-safe trays, and the microwave, paired with TV dinners, became a convenient solution for busy adults.

15. The Can Opener

Many years after people started storing food in tin cans, a way to open them without resorting to a chisel or hammer (or any other dangerous tool) was finally developed. In the mid-19th century, inventors came up with lever knives, not unlike the modern can opener found in Swiss Army knives. By 1870, William Lyman introduced a design that included a rotary cutter. However, it wasn’t until the 1920s that Charles Arthur Bunker patented a version with handles that could be squeezed to safely puncture the lid, and a twistable handle that propelled a sharp wheel along the rim. If that sounds familiar, it’s because today's manual can openers are essentially the same design.

16. Velcro

Much like the button (which dates back millennia, though the buttonhole is a relatively recent innovation) and the zipper (invented in the 1800s), Velcro changed the way we think about fasteners—and its invention is thanks to old-fashioned curiosity. In the 1940s, George de Mestral and his dog returned from a hunting trip covered in burdock burrs. Curious about why the burrs stuck to them, de Mestral pulled out his microscope and made a discovery: the burrs were covered with tiny hooks. This observation sparked an idea for de Mestral, a seasoned inventor: if he could create a fabric mimicking the burrs' hooks, and pair it with fabric loops for the hooks to latch onto, he’d have created a middle ground between buttons and zippers.

It took de Mestral a while to find a manufacturer willing to bring his idea to life, as many doubted it could be done. But he didn't give up. He kept refining his concept until he had a working product, and by the early '60s, Velcro—a trademarked term derived from the French words velours (meaning 'velvet') and croche (meaning 'hook')—was introduced to the market. It quickly proved to be as versatile as de Mestral had envisioned. NASA used it to secure equipment during space missions and moon walks; Mead incorporated it into its iconic Trapper Keepers; and of course, it became a staple in shoes and clothing, especially for people who have trouble with buttons and zippers (or their caretakers).

17. Air Conditioning

Since it was first introduced at the dawn of the 20th century, the air conditioner has greatly improved the quality of life in hot climates. However, the original purpose of the modern air-conditioning unit was not for human comfort but for industrial use in a printing press.

In 1902, a 25-year-old engineer named Willis Carrier was tasked with finding a way to control humidity at the Sackett & Wilhelms printing plant in Brooklyn, where the summer heat often caused issues with color registration. After experimenting with rollers, burlap, and calcium chloride brine, Carrier developed a system that circulated chilled water through heating coils. The system, installed that same summer, was complemented with fans and perforated steam pipes. It was an immediate success, providing the cooling equivalent of 108,000 pounds of ice each day.

Carrier's invention quickly found applications in industries ranging from flour mills to razor factories. Air-conditioning transformed architecture by making skyscrapers viable, allowing for comfortable top floors. It also played a key role in the growth of modern cities in hot regions like Singapore, Shanghai, the Sun Belt, and Dubai. Air conditioning improved everyday life for millions, if not billions. Ironically, the high energy consumption of air conditioners has contributed to climate change, increasing the need for cooling. As Malaysian architect Ken Yeang told The Guardian, 'It’s not a matter of going back to the past. But before, people knew how to work with the climate. Air conditioning became a way to control it, and it was no longer a concern. No one saw the consequences. People see them now.'

18. Radio

The invention of the radio is marked by a fierce competition between two scientists, where time was of the essence—and patents played a crucial role.

In 1894, Guglielmo Marconi, an Italian inventor, sent and received his first radio signals. He patented his creation in England in 1896, and just three years later, Marconi successfully transmitted wireless signals across the English Channel. A couple of years after that, he famously claimed to have received a message sent from across the Atlantic, though this claim remains disputed.

Meanwhile, across the ocean in America, inventor Nikola Tesla was working on a similar project. In the 1890s, Tesla developed the Tesla coil, a device capable of sending and receiving radio waves. He was preparing for a long-distance experiment in 1895, but a fire in his lab cut the project short. Two years later, Tesla applied for his own patent in the United States.

In 1900, the paths of Marconi and Tesla crossed when Marconi applied for a patent in the U.S., which was rejected because Tesla had already secured his earlier that year.

Despite this setback, Marconi pressed on with his efforts, and in 1904, the U.S. officially recognized him as the inventor of the radio. This, along with Marconi's Nobel Prize in the field, infuriated Tesla. In 1915, Tesla filed a lawsuit against Marconi for patent infringement, but he lacked the financial means to fully pursue the case.

Beyond the courtroom battles, radio was already making a profound impact on the world. In 1910, it played a key role in capturing Dr. Hawley Harvey Crippen, a man accused of murdering his wife and fleeing to Canada with his lover. His capture was made possible by Marconi’s wireless telegraph and a sharp-thinking ship captain. On August 31, 1920, Detroit became home to the first radio news broadcast, and in 1922, the first radio advertisement was aired, revolutionizing the advertising industry. Radio also served an essential role during both World Wars.

From protests and music to famous speeches and political unrest, radio has broadcasted countless iconic events, uniting the world in ways Marconi and Tesla likely never envisioned. Some claim that radio altered everything. As Jack Lule wrote in his book, *Understanding Media and Culture*, radio became 'an instrument of social cohesion,' connecting people from different backgrounds to experience the world as one nation.

Who triumphed in the radio patent dispute? In 1943, Tesla finally claimed victory when the Supreme Court ruled that his patent held priority. Unfortunately, Tesla was not able to celebrate this success as he had passed away earlier that same year.

19. Aquariums

Although keeping fish as pets dates back to Roman times, the first glass aquarium wasn’t created until 1832. This innovation came from Jeanne Villepreux-Power, a seamstress-turned-scientist who grew tired of studying dead specimens in her lab. Since observing marine life was more challenging than land animals, she sought a way to keep cephalopods, particularly the paper nautilus, alive outside of the ocean.

To advance her studies, Villepreux-Power designed three distinct types of aquariums: one for indoor research, another for shallow waters, and one meant to be anchored to the ocean floor. The indoor glass aquarium allowed her to observe that the *Argonauta Argo* created its own shell during the larval stage, and that the creatures could repair their shells within hours. She also proposed the idea of repopulating rivers with fish raised in aquariums. Unfortunately, most of Villepreux-Power’s research was lost in a shipwreck, and she never had the chance to rewrite her findings.

Many individuals would later build on her work, including Nathaniel Bagshaw Ward (who turned a terrarium upside down), Anna Thynne (who developed the first marine aquarium filled with coral and seaweed), and Robert Warington [PDF] (who published his findings after successfully maintaining a stable environment in a 12-gallon tank). Two decades after Villepreux-Power's invention, London opened the first public aquarium in 1853. Shortly after, P.T. Barnum built an aquarium inside his Barnum’s American Museum in New York, where it remained until the museum burned down in 1865.

Since then, aquariums have become a beloved hobby for people all around the globe. According to American Humane, 700 million people visit zoos and aquariums annually. Like zoos, aquariums play an important role in conservation and protecting endangered species. However, like zoos, they also spark controversy, as debates arise over the ethics of keeping large marine mammals, such as dolphins, orcas, and beluga whales, in tanks much smaller than their natural habitats. Despite this, many aquariums are dedicated to the same purpose Villepreux-Power had when creating the first aquarium: education and research.

20. The Lightbulb

Lighting a home was once a risky endeavor: Candles and open flames in fireplaces posed a real danger of setting everything ablaze. The gas lamp, which emerged at the end of the 18th century, was a marked improvement, but it came with its own set of challenges—ranging from harmful fumes and difficult maintenance to the potential for explosions.

Enter the lightbulb.

Although Thomas Edison is often credited with the invention of the lightbulb, he wasn’t the only one working on this idea. Several scientists and inventors had been exploring similar concepts before him. Humphry Davy, who created the arc lamp, showed that electricity could produce light. In the first half of the 19th century, multiple advances were made—so much so that Sir William Grove, later knighted, was able to give a lecture fully lit by electric light in the 1840s. However, the light was costly—up to 4 shillings per hour (the equivalent of 16 pounds or $22 today)—and the bulbs were both expensive to produce and unreliable.

The real breakthrough came in 1878 when chemist Joseph Swan replaced the costly platinum filament with a more affordable carbonized paper one that also lasted longer. Edison debuted his lightbulb in 1879, a year after Swan. After a lengthy legal battle over patent rights, the two inventors decided to collaborate and formed the Edison-Swan United company. In his later years, Edison would call his lighting system his greatest invention.

Even though Edison and Swan’s bulb wasn’t flawless, many other scientists continued refining the design. One such contributor was patent expert Lewis Latimer, who enhanced the carbon filament by encasing it in cardboard instead of bamboo. This simple but significant modification allowed bulbs to last much longer.

It's no exaggeration to claim that the modern lightbulb revolutionized society. Beyond simply making homes safer, it helped reduce health issues related to gas fumes and smoke inhalation, facilitated longer working hours, influenced building designs, and sparked the development of major infrastructures like the electric grid. Lightbulbs found their way into everything from cars to airplanes to trains, accelerating travel and making it much safer. The lightbulb also holds a lasting symbolic significance. As Ernest Freeberg, author of *The Age of Edison: Electric Light and the Invention of Modern America*, remarked in 2015, "Even though this invention, Edison’s bulb, is 135 years old at this point, we still use [it] as the universal symbol for a great idea, for a stroke of inventive genius, for this Eureka moment." Today, scientists continue to refine the lightbulb each year, making it more energy-efficient and contributing to the legacy of the many scientists and engineers whose innovative ideas have shaped history.