What if your body’s greatest defender turned into your worst enemy? That’s the nightmare of autoimmune diseases, where your immune system mistakes you for the threat. In this video from Kurzgesagt, we learn how conditions like Type 1 diabetes, multiple sclerosis, lupus, and Crohn’s disease aren’t caused by invaders but by your own cells going rogue.

Your immune system is a terrifyingly efficient army of cells trained to kill anything unfamiliar. But sometimes, through genetic risk and a dose of bad luck, that army gets the wrong orders. One mistaken identity, one unlucky cold, and boom, your body launches a full-scale assault on your nerves, joints, pancreas, or anything else in range.

This explainer breaks it all down with vivid analogies (think baristas under sniper fire) and clear science. Check it out!

What do rocket payloads, car airbags, and intricately folded paper dragons have in common? All of them owe something to the genius of Robert Lang, a physicist, laser expert, and former NASA engineer who walked away from a high-tech career to chase his childhood passion: origami. But he didn’t leave the science behind. He brought it with him, turning the ancient art of paper folding into a cutting-edge tool for solving some of modern engineering’s most complex problems.

In this Great Big Story documentary, we follow Lang’s remarkable transformation, from a NASA researcher with 46 patents in semiconductor lasers, to a world-renowned origami master. But don’t expect simple swans and cranes. Lang’s work blends traditional Japanese craftsmanship with advanced mathematics, unlocking folding patterns that help satellites unfold in space and airbags deploy with precision.

By studying the geometry of folds, Lang has opened up a universe of practical applications. Whether he’s creating lifelike insects or designing compact structures that spring into action, he proves that paper isn’t just for art, it’s for innovation.

Watch the full video and prepare to have your mind folded.