are one of those things that are easy to forget about. They live silently in your dash or steering wheel, biding their time until that one incredibly important moment when they’re expected to work flawlessly and save your life.

What’s incredible is that they sit untouched and unnoticed, sometimes for decades, in freezing cold and incredibly hot temperatures, and barring those from , they just work. But how do they work?

I’m a pretty big nerd. I love automotive engineering, and I read technical stuff all the time, both for work and fun, so I thought I understood airbags, but there’s a lot more there than I realized, both in their operation and design and their history.

This video from the YouTube channel New Mind is a little dry (except when they use a background photo of a car with the license plate “ASSMAN,” which is hilarious), but it’s also remarkably thorough and ultimately pretty interesting. For example, I didn’t know that as an option in its full-size cars in the ‘70s before discontinuing it in 1978.

I also learned that the two initial patents for automotive airbags were issued independently just a couple of months apart in the 1950s or that vehicle manufacturers in the 1990s could choose between fitting airbags to their cars or automatic seatbelts. I just assumed had automatic seatbelts as a cool gimmick, not because it was cheap. Also cool is the fact that the 1987 Porsche 944 Turbo was the first car to have standard driver and passenger airbags.

I’ve been really lucky and have never been in a crash where I’ve had an airbag deploy, but I find it strangely comforting to have a much better understanding of how they work. Hopefully, you do too.