Casinos are entertainment meccas that bring in billions of dollars every year from gamblers who place bets on everything from the latest sports event to a game of blackjack. While lavish hotels, musical shows, lighted fountains and shopping centers draw in the crowds, casinos would not exist without their main attraction: games of chance.

Gambling has been part of human society for millennia. Archeologists have found wooden blocks used in gambling in China from 2300 BC, and dice appeared in Rome around 500 AD. Cards hit the scene in the 1400s, followed by baccarat in the 1600s and the modern-day card game of poker in the 1800s. Today, casino gambling is ubiquitous, with a multitude of slot machines, video poker, table games and more.

Modern casinos are heavily guarded. Security begins on the gaming floor, where employees keep their eyes on patrons for any blatant cheating, including palming and marking, as well as looking for bet patterns that could signal crooked dealing. The casino manager and pit boss also monitor tables with a broader view, watching for any crooked behavior.

Many casinos have a wide variety of non-gambling activities as well, from golf courses and restaurants to spas and rooftop pools. They host top acts like Cirque du Soleil, Elton John and Mariah Carey and feature world-class sports and horse racing. They offer a wide range of dining options, from award-winning steakhouses to casual breakfast bistros and sushi bars.