I would like to know how the computers on Powder Toy work. I really want to make one, but I have don't even know how they work. Thanks
there are a few wiki threads on logic circuits, they're extremely helpful if you don't know where to start.
https://powdertoy.co.uk/Wiki/W/Creating_Logic_Circuits.html
https://powdertoy.co.uk/Wiki/W/Complete_Electronics_Tutorial.html