Any scientist will tell you that their job involves a lot of trial and error. And while many major discoveries have been the result of long hours in the laboratory, revised calculations and recalibrations, just as many scientific breakthroughs have happened completely by accident. In fact, many scientific leaps forward have happened as scientists were working on something completely different and unrelated to their most famous discovery. And it may surprise you what major achievements that we all rely on today for our health and comfort were the result of happenstance. Here then are 10 scientific breakthroughs that were happy accidents.

10. Velcro

Velcro, the two-way material that enables young children to do up their sneakers without laces and is featured on clothing items ranging from jackets and pants to hats, was created by Swiss engineer and scientist George de Mestral in 1941. One evening, after a hard day at his lab, Mestral was out walking his dog through a field when he noticed seeds of burdock stuck to his flannel trousers. He took the seeds to his lab the next day and examined them under a microscopic lens, where he noticed that the “hooks” of the seeds would stick to anything with a loop. Thus was born the synthetic material that is a feature of outdoor and indoor clothing to this day.

9. Viagra

Known as a lifestyle drug and the saviour of aging men everywhere, the drug Viagra, which treats erectile dysfunction, was discovered completely by accident during the early 1990s. Scientists employed at pharmaceutical giant Pfizer were actually working on a heart medication to treat the condition angina, which is a painful heart ailment where not enough oxygenated blood is circulated into the heart. However, to the scientists’ surprise, the pill they developed had an unusual side effect. In patient trials, it was discovered that the angina pill increased blood flow much lower than the heart to the men’s groin area. At first, the scientists planned to scrap the pill as a failure until they noticed that the elderly men in the trial reported great satisfaction with the unintended side effect. And so a blockbuster lifestyle drug was born.

8. X-rays

Today, X-rays are ubiquitous in medical care around the world. Doctor’s offices and hospitals everywhere use X-ray machines to peer inside the body and examine human bones and skeletons. However, there was a time before X-rays when it was impossible to see beneath the human skin without cutting a person open. Fortunately, in 1895, a German physicist named Wilhelm Röntgen was playing with a tube of cathode rays, which are used today in television sets and florescent lights, when he left it in a black box in his lab and happened to notice something peculiar when he switched off the lights on his way out the door one night. The tube of cathode rays was glowing. On further examination, Wilhelm realized, to his own surprise, that a photographic plate covered in barium platinocyanide was causing the glowing light. He then decided to name the unknown radiation causing the glowing effect, calling it “X-ray.” And, with further investigation, Wilhelm Röntgen realized that he could use this process to photograph the inside of the human body. Using his wife as a guinea pig, he took an X-ray of her hand—the first ever X-ray image. The rest, as they say, is history. This accidental breakthrough earned Wilhelm Röntgen the first Nobel Prize in Physics in 1901.

7. Dynamite

Although best known for the Nobel Prizes he founded in 1895, Alfred Nobel was actually a Swedish chemist and engineer who worked primarily in armaments manufacturing and is credited with discovering Dynamite. And while he held 350 scientific patents during his lifetime, he is best remembered for his discovery of the explosive element, which, as it turned out, occurred by accident. In the mid-1800s, Nobel was working with nitroglycerin in an attempt to make the explosive substance more stable and safe for people who used it to blast their way through rocks to create railroad tunnels. However, after accidently dropping a vile of nitroglycerin into some sawdust on the floor, Nobel realized that he was still alive. This experience taught him that mixing nitroglycerine with an inert substance such as sawdust could make it more stable, eventually leading to his creation of Dynamite sticks. Of course, this proved to be a major breakthrough and Dynamite was used widely in construction. But Dynamite was also used by militaries as a weapon, something that did not sit well with the scientist in Alfred Nobel. To make up for his dangerous invention, he founded the Nobel Prizes, the most prestigious one being the annual Nobel Peace Prize, awarded to a person(s) who stops conflict and spreads peace in the world.

6. Phonograph

American inventor Thomas Edison had many notable inventions during his lifetime—most of them deliberate. However, one of his biggest and most influential inventions was a complete accident. We’re speaking here of the Phonograph, which was the first invention that enabled the recording of sounds and voices and paved the way for everything from recorded music to sound in movies. In the summer of 1877, Thomas Edison was playing around in his lab with a tinfoil and paper cylinder that he was hoping would record telegraph signals. By accident, and to his great surprise, Edison recorded his own voice—the first time that a human voice had been recorded. Even stranger, Edison was able to play back the recording to himself. This led to the invention of the Phonograph, which was perfected at Alexander Graham Bell’s Volta Laboratory and led to the first record players and musical records.

5. Vulcanized Rubber, aka Tires

The name Goodyear is synonymous with car tires, and for good reason. American Charles Goodyear was a chemist and manufacturing engineer who had spent years trying in vain to make a rubber that was durable, pliable and easy to work with. He wanted a synthetic rubber that would not be impacted by heat or cold. Yet his many experiments went nowhere. That is, until he accidentally spilled a mix of rubber, lead and sulfur on the stove in his kitchen at home. Rather than spoil the solution, the combination and heat charred it together into a leathery substance that accomplished Goodyear’s goals. Today, vulcanized rubber is used in all types of automotive tires, as well as the soles of shoes and many, many other products.

4. Teflon – Non-Stick Coating

In 1938, Roy Plunkett, a scientist with the DuPont chemical company, was working on ways to make refrigerators safer for use at home. At that time, the main ingredients used to keep refrigerators cool were ammonia, sulfur dioxide and propane, which could prove to be a dangerous mix. Playing with many different gas combinations, Plunkett opened one container of a sample he’d been tinkering with and noticed that his experimental gas was gone. All that was left was a strange, slippery resin that was resistant to extreme heat and chemicals. Plunkett named the resin Teflon, and its first use was in the Atomic bombs developed by the U.S. in the 1940s as part of the infamous Manhattan Project. After World War II, Teflon was then used in the automotive industry to make cars and trucks. It wasn’t until the 1960s that Teflon was adapted and used to create non-stick cookware. Professional and amateur chefs the world over are grateful for this accident.

3. Coca-Cola

Today, Coca-Cola is the leading soft drink in the world and an elixir that is enjoyed by many. However, Coca-Cola was originally developed by a pharmacist as a medicine to cure headaches. John Pemberton was a pharmacist from Georgia, and a Civil War veteran, who was searching for a cure to the common headache in 1886. Pemberton used two main ingredients in his elixir that he hoped would be a headache cure: coca leaves and cola nuts. Thus the medicine was named “Coca-Cola.” However, when a lab assistant of Pemberton’s accidentally mixed the two ingredients with carbonated water, the world’s first soft drink was invented. And Coca-Cola went from being a medicine to a recreational soft drink. Today, Coca-Cola is a global empire and giant in the food and beverage industry. However, John Pemberton never got to see this happen. He died two years after the drink was invented and never saw his simple mixture give birth to a worldwide soft drink industry.

2. The Microwave Oven

The microwave oven is a fixture in almost every American home today. However, this convenient appliance came about completely by accident. Engineer and scientist Percy Spencer was working at defense contractor The Raytheon Company in 1945 when he walked in front of a magnetron, which is a vacuum tube used to generate microwaves, and noticed that the chocolate bar in his breast pocket melted. A flurry of experiments involving heating food and exploding eggs quickly followed this discovery, and by 1947 the first microwave oven had been invented. And it was a beast. The very first microwave oven stood six feet tall, weighed 750 pounds and cost $3,000.00 (1947 dollars!). However, by 1967 a compact microwave oven was made commercially available to the American people and the’ve been using the device to reheat food and make popcorn ever since.

1. Penicillin

Invented in 1928, Penicillin revolutionized medicine and has saved countless lives since its discovery. The first antibiotic, it continues to be used to treat infections and bacteria around the world. However, Penicillin came about completely by accident. Scottish scientist and Nobel laureate Alexander Fleming went on a month-long holiday in 1928 and accidentally left a number of bacteria cultures out on the counters of his laboratory—something scientists are told never to do. Returning from vacation, Fleming noticed that one culture had developed mold and that the mold had destroyed all the bacteria colonies around it. After growing the mold again in controlled conditions, Fleming found that it formed “mold juice,” which would go on to kill a number of disease-causing bacteria. By 1942, Penicillin was being used to treat infections and today it is a cornerstone of antibiotics the world over. And all because a young scientist did not clean his lab properly before going off on vacation.