What the hell is ''BOP'' ?

What is this "Burden of Proof'' ? Is it some sort of pass-code to another dimension ?

RXR.: It's a tool some judges use. It's the side with the BoP (almost always pro) that ultimately must prove their case in order to decide a winner. This helps resolve equal situations in formal judging on balance of probabilities.

The same is also sometimes applied outside of debating in logic - the person bringing the claim must be the one to provide evidence.