The first thing to do when you arrive in Tokyo is to know and to get around: the city is served very well by public transport. For this reason, if you stay in Tokyo for a few days, it is advisable to buy one between the Pasmo and Suica, rechargeable cards that can be used on all urban public transports and that can be recharged without problems to the machines located in all the stations. There is no difference between Pasmo and Suica except for the refund process at the end of your trip since the Pasmo can only be returned within Tokyo Prefecture, including airports. You've read correctly: the cards are returned at the end of your trip directly at the airport and if there are any remaining money, cash will be returned, together with the initial deposit. The machines for purchase can be found at the airport and at all stations, where they can also be refilled by following the instructions in English.