Quote Originally Posted by Random_Hero
whats an "overlay"?
in a hand of poker overlay is usually the money currently in the pot.

Example, if you are in the bb in a donkament with T7o, the blinds are 200/400/25ante, and a 1200 stack goes all in, it folds to you. You are almost certain that his hand beats you, yet you still must call because you are getting ridic good pot odds, the 800ish worth of overlay (your posted bb, the posted sb, and 8-9 25 antes) is forcing you to make a plus ev call.

Also, overlay exists in a different way in an unprotected pot when you are semibluffing. You might decide its a good idea to bet/3bet all in on someone with nothing but a flush draw (32% chance of winning when all in), you figure he folds enough so that the overlay pays you off well enough that you don't care the times he calls and you have to gamble.

Also, whenever you make any bet with positive expectation, the amount you are profiting is considered overlay. Like if i were dumb enough to propose that if you bet 1 dollar that this coin comes heads when i flip it, i'll give you a 10 dollar bonus whenever it comes heads twice in a row, then that 10 dollars would be overlay on your neutral ev proposition (flipping a coin for 1 dollar), and turning it into a very plus ev proposition.