A vending machine is a mechanical and self-operating machine, which dispenses a product whenever a customer inserts money into it. Vending machines include a currency detector, which confirms whether the amount of money deposited is enough to purchase the desired item.

Vending machines are generally placed in busy and high-traffic locations including: in or near restrooms, in break rooms, next to entrances or exits, by coffee makers, next to change machines, next to listening stations at music stores, next to water fountains, nearby the receptionist area, next to other vending machines, next to cash registers, or near waiting areas.

The types of products sold through vending machines vary. In western countries such as the U.S., vending machines commonly sell snacks, beverages, newspapers or even instant photos. Vending machines may even sell alcoholic drinks and cigarettes though this is no longer encouraged because of underage buyers.

In Japan, vending machines are widely used because of its highly mobile population that prefers to shop on the go on foot or by bicycle. In fact, Japan has the highest number of vending machines per capita, with about one...