How to Read Slots Paytables? Since slots first became prominent midway through the 20 th century, they have always been incredibly easy to understand. When it comes to class II slot machines, these can be mostly found on Indian gaming reservations and illegal gambling establishments as well as unlicensed online casinos, where state regulations don't apply. All casino games, including slots, offered by licensed online casinos, also work on the same principle as class 3 slot machines.
