# Zero Knowledge - Who is greater?

I just encountered the term "zero-knowledge" and wanted to know more about it.

I understood that there is a zero knowledge protocol between two parties to determine whether $x$ is greater than, equal to, or smaller than $y$, given that one side knows $x$ and the other knows $y$, but I couldn't find anything about it.

Hopefully you guys can give me a simple answer.

I believe that, for your problem, it is not zero knowledge what you're looking for. Look instead for multiparty computation, but beware: this is a huge research area. In MPC, you want multiple entities to interact, but you know that some of them can cheat in very different ways. The literature is strongly associated with e-voting. You will meet there with Zero Knowledge, but also with homomorphic encryption, commitments and other concepts. You'll be specially interested in oblivious transfer: Bob knows a function $F$. You, Alice, want to get the value of $F(n)$ without telling Bob the value of $n$.