The Octopus card is a smart card used for electronic payments in Hong Kong. It was introduced in 1997 and is primarily used for public transportation, including buses, trains, and ferries. The card can also be used at various retail outlets, restaurants, and vending machines, making it a convenient payment option for residents and tourists alike. The card operates on a contactless system, allowing users to tap it on a reader to complete transactions quickly. Users can add value to their Octopus card at designated machines or retail locations. Its widespread acceptance has made it an essential part of daily life in Hong Kong.