The word comes from the Southern Song Dynasty proverb "bento", which means "convenient things, convenient and smooth". After it was introduced into Japan, it was marked with the words "access", "distinguishing the way" and "distinguishing the time".

The word "bento" later came back to China, because it originated from the Japanese word "dang" (new font: dang, old font: bian dang), even when it was called bento in Chinese mainland, it was called lunch box in Hong Kong; In early Taiwan Province Province, it was called rice bag in Minnan dialect, but it was often called bento because of the influence of Japanese occupation.

Lunch boxes are usually used for lunch and dinner. They are not used at home or eaten in restaurants, that is, takeout and picnics. To save time and work such as cooking and washing dishes. You can buy a ready-made lunch in the store, or call the take-away shop, or go to the buffet to choose your favorite side dishes. Bento is also one of the ready-to-eat goods sold in convenience stores.

In Taiwan Province Province, before nutritious lunches were popularized in schools at all levels, many students took homemade lunches to school. Usually put it in a steamer in the morning, and then bring the steamed lunch to eat at noon.

In Japan, both homemade lunches and take-out lunches are mostly cold lunches, and a few take-out lunches are equipped with heaters, which are heated by chemical exotherm; In greater China, it is mainly a hot lunch.