ELI5: Explain Like I'm 5

Church–Turing thesis

The Church-Turing thesis is an idea from computer science that says that any problem that can be solved using a computer can also be solved using a very simple kind of machine called a Turing machine. This machine only has a few parts and it can solve any kinds of problems. The thesis even says that the same machine can be used to do math, play chess, and even write a poem. So, it's like a super-smart machine that can do a lot of really cool things!