Markers are money borrowed from a casino to gamble, functioning like a short-term loan. This guide covers the different types of markers, the borrowing process, the consequences of defaulting on markers, how casinos use markers to track player activity, and the pros and cons of using markers for high rollers. Players must understand the implications of borrowing from a casino, including credit checks, repayment schedules, and fees, and utilize effective strategies to manage markers responsibly.