"Coin-operated" refers to machines or devices that require users to insert coins to function. Common examples include vending machines, arcade games, and laundry machines. These machines are designed to provide a service or product in exchange for a monetary payment, making them convenient for users who need quick access to items or entertainment. The concept of coin-operated devices dates back to the late 19th century, with the first known coin-operated machine being a penny-in-the-slot device. Today, many coin-operated machines have evolved to accept various forms of payment, including credit cards and mobile payments, but the traditional coin mechanism remains popular in many settings.