An Oyster card is a contactless smartcard used for travel on public transport in London. It can be used on the Underground, Overground, DLR, London Buses, trams, and most National Rail services within London. Oyster cards can be purchased at Underground and Overground stations, as well as at many newsagents and convenience stores.
There are a number of benefits to using an Oyster card. First, it is more convenient than using cash or a credit card, as you do not have to queue to buy a ticket every time you travel. Second, Oyster cards offer a discount on fares compared to using cash or a credit card. Third, Oyster cards can be used to store multiple tickets, including Travelcards, which can save you even more money.