Okonomiyaki is a Japanese savoury pancake containing a variety of ingredients. The name is derived from the word okonomi, meaning "what you like" or "what you want", and yaki meaning "grilled" or "cooked" (cf. yakitori and yakisoba ). Okonomiyaki is mainly associated with Kansai or Hiroshima areas of Japan, but is widely available throughout the country. Toppings and batters tend to vary according to region.
In Hiroshima, the ingredients are layered rather than mixed together. The layers are typically batter, cabbage, pork, and optional items such as squid, octopus, and cheese. Noodles (yakisoba, udon) are also used as a topping with fried egg and a generous amount of okonomiyaki sauce. The amount of cabbage used is usually 3 to 4 times the amount used in the more common Kansai style. It starts out piled very high and is pushed down as the cabbage cooks. The order of the layers may vary slightly depending on the chef's style and preference, and ingredients will vary depending on the preference of the customer. This style is also called Hiroshima-yaki or Hiroshima-okonomi.
(Definition by Wikpedia)