Numerous manufacturers & innovations emerged in the early 20th century as a result of the growing variety of designs & themes that accompanied the popularity of these machiwinfortune slotsnes. Slot machines saw substantial changes as the decades went by, especially in the US during the Prohibition period. Slot machines became a popular source of income for many establishments when traditional gambling venues were subject to restrictions. As a result, fruit symbols were added to these devices to cover up their gambling content.