There are three main bills in Japanese yen. 1000 yen bills, 5000 yen bills, and 10000 yen bills. You will use the 1000 yen bill basically every day, and if you are lucky, you'll hopefully see a lot of the other two, as well.

During the two weeks I was in Japan, I kept looking at the bills and wondering who the people on them were. On the money from every other place I've gone, (Swiss Franc, Tanzanian shilling, Kenyan shilling, American dollar, Euro) I've just googled the name under the picture on the bill if I got curious, but I can't read Japanese, so I never found out who the faces on the yen belonged to. But now I know, and I can spread the knowledge.

1000 Japanese yen
The 1000 yen Japanese bill is blue and it equals around ten Canadian dollars. The guy on the bill is named Hideyo Noguchi. He was the bacteriologist who discovered Syphilis in 1911.

5000 Japanese yen
The 5000 yen Japanese bill is kind of a purple-ish color and equals around fifty Canadian dollars. The woman on the front is Higuchi Ichiyo,a famous writer who died of Tuberculosis. She's not the first female writer in Japan, or the most prolific, but she is well respected and one of three women to even be featured on a Japanese yen bill. She is really pretty on the bill.

10,000 Japanese yen
The 10,000 yen Japanese bill is a tan color and equals around one hundred Canadian dollars, and features a picture of Fukuzawa Yukichi:
"Fukuzawa Yukichi was a Japanese author, writer, teacher, translator, entrepreneur and political theorist and founder of the Keio University whose ideas about government and social institutions made a lasting impression on a rapidly changing Japan during the period known as the Meiji Era. He is regarded as one of the most influential thinkers in Japan and during the Meiji Restoration, which is a source of pride for many modern day Japanese people. He is regarded as one of the founders of modern Japan, and is highly respected in Japan." -Wikipedia

The Best Yen
Japanese kids know that the best bill of all is the 1000 yen bill. Japanese kids know how to fold this bill to make Hideyo Noguchi happy or sad. It's actually really funny.

Now Hideyo Noguchi is happy. He discovered Syphilis in 1911!

Now Hideyo Noguchi is sad.

1000 yen bill wins for coolest bill. Ask any kid.