Musubi (aka omusubi or onigiri) is a Japanese rice ball that is mixed, filled, or topped with a variety of ingredients and sometimes wrapped in nori.
People began making musubi as food to take into battle because of their portability and ability to keep throughout the day.

Fossilized rice balls have been found throughout Japan and it is estimated that musubi originated in the Iron Age (300 BC - 300 AD). In the Edo era (17th -19th centuries) musubi remained popular with farmers & travelers. In the late 19th century, musubi was brought to Hawaii by Japanese immigrants and was often prepared as a convenient lunch while working the plantations.

Today in both Japan and Hawaii musubi remains a staple that can be found in restaurants, markets, and convenience stores for a satisfying and affordable breakfast, lunch, or snack.