Coin-operated machines are 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 want quick access without needing a cashier. The concept of coin-operated machines dates back to the late 19th century, with early versions found in London and New York. Over time, they have evolved to include digital payment options, but the traditional coin mechanism remains popular in many settings, offering a simple and straightforward way to make transactions.