Chances are, you probably use things like Post-its and your microwave every day without thinking twice about where they come from or how they were invented. You might be surprised to learn, though, that some of the world's most popular products weren't originally intended for the things we use them for now—and some others weren't even meant to be invented at all. Here is a look at the shocking origins of four everyday products that will change how you think about them forever.

Post-it Notes

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Like penicillin, and many other things that have become essential for our survival, Post-it Notes were invented by accident. Or, to be more precise, the not-too-sticky but just-sticky-enough glue on the back was invented on accident by 3M employee Spencer Silver in 1968. No one could think of a use for this glue until 1974, when his coworker Arthur Fry decided to use it as a way to keep his bookmarks in place when he was using his hymnal at church. The resulting invention was viewed with skepticism at first, but soon became one of the most popular office supplies of all time.

Corn Flakes

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In the 1950s, breakfast included sausage, eggs, bacon, toast, pastries, and a myriad of other things, all of which sat very heavy on the stomach and led to some pretty bad indigestion. For health reformers like sanitarium worker William Kellogg, the solution to this problem was to make simpler, easier-to-digest foods. Kellogg and his brother, John, attempted to make a wholesome vegetarian breakfast option by boiling some wheat in an effort to make dough. Unfortunately (or fortunately for us), they let the wheat boil too long. When they went to roll it out, it broke into flakes instead of a long, uniform stretch of bread dough. Instead of getting upset, they decided to bake it anyway, and once they tasted it, they decided that it was delicious and gave it to their patients. The patients loved it, just like the rest of the country did when they started selling it commercially a few years later.

Artificial sweeteners

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This one is a little unsanitary. Saccharin, an artificial sweetener that is often used instead of cane sugar, was invented by accident when a chemistry professor forgot to wash his hands. In 1878, chemist Constantin Fahlberg was working on some experiments that tested the purity of some sugar shipments his company had received, as well as on other experiments that involved things like coal tar. One day, when he took a bite of his bread roll at lunch, he noticed that it tasted very sweet. After ascertaining that it wasn't the bread that was different, he realized that he must have spilled a chemical on his hands while he was working. Instead of freaking out, though, he went back to his lab and started tasting every chemical he had (don't try this at home!) until he finally discovered that it was a mixture of ulfobenzoic acid, phosphorus chloride and ammonia he had been working with. He patented the creation and was the first to release an affordable artificial sweetener to the world.

Microwave oven

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You would be hard-pressed to find a single house in the the world that doesn't have a microwave in it. This magical device can make popcorn in mere minutes and heat up food in seconds, as opposed to the hours it could take in a conventional oven. What makes it even more magical, though, is that it was invented by accident. When Percy Spencer was working for a company called Raytheon during World War II, he was tasked with developing microwave radar transmitters. One day, while he was working, he noticed that the microwaves he was using were melting a candy bar he had in his pocket. This filled his mind with infinite culinary possibilities, and he used his research to concentrate the microwaves in such a way that they could be used to cook food on purpose. And what was the first food he cooked up in the world's first microwave oven? Popcorn, of course!