How can people make fully functional games on computers in the first place?
The answer is logic gates. The ability to have 2 certain inputs affect a certain output in a few ways is all that is needed.
As long as logic gates can be chained together (usually in the count of thousands or millions is useful) a computer can be made. And once the computer is made, a game can be added to it.
In real life, the logic gates are made out of transistors. In Minecraft, the way its redstone interacts can be combined to create logic gates.
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