The house edge is the advantage a casino has over a player in each and every game available to play. Casinos don't make money when a player makes a deposit, they are simply holding the cash, they make money through players playing the games with that unavoidable house edge.
While gaming has been popular since the earliest cultures in places like ancient China and ancient Rome, casinos didn't enter the picture until 1638. Meant to provide fun and entertainment during downtimes of the Venetian Carnival, Il Ridotto had some very strict rules.