O-nigiri , also known as o-musubi, nigirimeshi or rice ball, is a
Japanese food made from white rice formed into triangular or cylinder shapes
and often wrapped in nori (seaweed). Traditionally, an onigiri is filled
with pickled ume (umeboshi), salted salmon, katsuobushi, kombu, tarako, or
any other salty or sour ingredient as a natural preservative. Because of the
popularity of onigiri in Japan, most convenience stores stock their onigiri
with various fillings and flavors. There are even specialized shops which
only sell onigiri to take out. Due to its popularity in Japan, the trend of
small restaurants and convenience stores selling onigiri has traveled to
other parts of the world, such as Taiwan, China, Hong Kong, South Korea,
Thailand, Switzerland, Hawaii, New York City, London, Australia, Canada, and
parts of California.