1.House Edge (or Vigorish): This is a mathematically determined advantage that the casino has over the player in all their games. It's built into the rules and odds of every game.
2.Long-Term Profit: While individual players can certainly win big in the short run, the house edge ensures that the casino will make a profit over the long term, as the aggregate losses of all patrons will exceed the aggregate winnings.
3.This is the percentage of wagers that a game is expected to return to players as winnings. It is always less than 100% due to the house edge.
