If you want to talk about Japanese foods you need to know about pickled ginger.
Ginger roots have thin or thick skins, depending on their level of maturity when they were harvested. You should check these out when you buy your ginger to make sure they look healthy and mold-free, and peel the skin off before you use it.
Young ginger roots are very juicy, yet mild. You can enjoy young ginger pickled (like when you eat sushi) .