The differences between piston and rotary engines

I’d never heard of a rotary engine before today. Saw an interesting cross section of one somewhere and just through it was interesting. Searched, read a bit, and then found this:

I love discovering things that I don’t know. And especially like this, when I wager there are millions of people that know this subject inside out, and who would likely be dumbfounded that I’d never heard of rotary engines before.

There’s something comforting about discovering your own ignorance of a largely know subject. Like there’s always more to the world than you realise. More to learn and more to rely on each other for. Can’t do or learn it all alone.