Japanese currency is the Yen. At present there is about
100 Yen equals about $1.00. If I remember correctly, 100 Yen is a coin, the smallest denomination of paper currency is 500 yen, or about $5.00. Coins in Japan are 1 yen, 5 yen, 10 yen, 50 yen, and 100 yen. Paper currency is Y500, Y1,000, Y5,000, Y10,000, I don't remember for sure, but its easy to check what the bigger denominations are. Just call your local bank.