If you want to speed up your travel, purchase a PASMO or SUICA card. They'll help you get around and it's amazing what you can use them for: train and bus travel, drink ... and McDonalds! This video will show you how to purchase one. We think it'll be helpful.
* IC cards are named differently (Kitaca, TOICA, ICOCA, SUGOCA, manaca, PiTaPa, Hayakaken, or nimoca) outside of the Kanto Plain, but interoperable. If you have one of them, you can use it almost anywhere in Japan.