You are strongly advised to purchase an Octopus debit card to facilitate your transport in Hong Kong. These may be purchased from customer service counters at Mass Transit Railway (MTR; metro) stations, as well as at the Arrival Hall of the Hong Kong International Airport. The Octopus can be used in most all public transportation in Hong Kong, as well as in most convenience stores, supermarkets, etc. Please visit the following link for more information: http://www.octopus.com.hk

Note: all transportation costs quoted above assume that you are using an Octopus Card. Single journey tickets are generally more expensive. Before you leave Hong Kong, remember to return your Octopus to one of the customer service counters to get a refund on your deposit and unused credit.