Coming from NYC and being used to swiping once to pay a flat fair, my first Suica lesson was they vary the fair by the distance traveled. This means you have to tap in AND out of buses and subways. It was a bit embarrassing and frustrating when I almost could not board a bus in Sapporo with my friends after they all tapped in and my card was rejected. WTF? Thankfully the bus driver showed me a sign in English telling me I forgot to tap out of a station or bus. Oh. He let me board the bus with my friends. Found a train station and the woman at the counter began holding up a series of English signs so we could figure out where I forgot to tap out to ensure the correct charge is applied then sent me on my way. Turns out I goofed up transferring between the Tokyo subway and Shinkansen where I didn't tap out of the subway, got stuck, and a frustrated transit worker just opened the gate to let my dumb tourist ass through meaning I didn't tap out of the subway.

I was floored when I found out you could pay for stuff with my "Japanese MetroCard." It's quite a wonderful system.