Japanese noodles (see noodles of japan) made from wheat flour. They are similar to spaghetti but softer in texture.
Udon are said to be of Chinese origin, introduced to Japan during the Chinese Tang dynasty (618–907). Contemporary documents suggest that the original udon was not noodles but pieces of rolled-out dough wrapped around fillings, like Chinese wonton. (The words ‘udon’ and ‘wonton’ have a common root.) It is not clear when udon came to mean noodles as it does today. Udon as noodles seems to make its first appearance in the first half of the 14th century. According to some sources, it was eaten mainly by Buddhist monks and gradually spread amongst ordinary people. This is not unlikely, since there were close links between Buddhism and Chinese culture at the time.