Donburi (Rice bowl)
Oyakodon

Oyakodon
Oyakodon is a dish that chopped chicken, beaten egg and chopped onion are all simmered together in a sauce of dashi, shoyu and mirin, then are served on the top of rice in a donburi.
"Oyako" means "parent and child", and it comes from using both chicken and egg as main ingredients.
You can eat Oyakodon at the following chain restaurants.
Gyudon

Gyudon
Gyudon is the dish that sliced beef and chopped onion are all simmered together in a sauce of dashi, shoyu and mirin, then are served on the top of rice in a donburi.
The taste is similar to "Sukiyaki".
Gyudon is often called "beef bowl" in English.
In Japan, it can be found in many Japanese restaurants and some fast food chains specialize exclusively in the dish.
The followings are the main Gyudon chain restaurants.
Some of them may exist in your country as well.
Katsudon

Katsudon
Katsudon is the donburi that Tonkatsu (Japanese pork cutlet) is put on rice.
To season the tonkatsu, it is simmered with beaten egg and sliced onion in a sauce of dashi, shoyu and mirin.
"Katsu" has the same sound as the word for "win" in Japanese, so students taking an entrance exam and athletes somtimes eat it before their fights.
There are several katsudon chain restaurants.
Also, because it uses Tonkatsu, it's often found on the menus of specialty Tonkatsu restaurants.
(Most of them are Japanese websites.)
Tendon

Tendon
Tendon is a combined word of the head parts in "Tenpura" and "donburi".
It is the dish that some kinds of tenpura are put on the top of rice.
A little sauce of shoyu and mirin are poured to season the tenpura.
Generally main ingredients of tempura are one or two prawns and a few vegetables.
Tenpura restaurants often serve Tendon as lunch menu.
And soba noodle restaurants sometimes serve Tendon and sobe noodle as a set menu.
The following is the main Tendon restaurant chines.
Unadon, Unajū

Unaju
"Una" is abbreviation of "unagi" which means eel, so Unadon is the donburi which kabayaki eel is put on the top of rice.
Kabayaki is a cooking method to broil a fish after pouring the sauce of shoyu and mirin over.
This is the basic way that Japanese people cook eel.
Also Unajū is the same dish, but it is served in not a donburi but a lacquer box (jūbako in Japanese).
Eel dishes are expensive in Japan.
This is a slightly luxurious fast food option for Japanese people.
Jūbako allows for neat arrangement of eel toppings and also adds a touch of luxury.
So, Unajū is a little more expensive than Unadon.
These are the main dishes at eel specialty restaurants.
Kaisendon

Kaisendon
Kaisendon is a donburi dish that various sushi toppings are put on the top of rice.
"Kaisen" means "seafoods".
Sometimes vinegared rice is used for the rice.
Various fish are put in a donburi, so it is very colorful.
In a sense, it might be like eating various kinds of sushi without actually making them yourself.
It is often served as an affordable lunch option at sushi restaurants.

Tekkadon
Maguro (tuna) is the most popular Sushi topping.
There is a donburi dish of only maguro.
It is called Tekkadon or Magurodon.
Although it is a type of Kaisendon, this donburi is often listed on menus under these names.
Sushi chefs recommend that when eating Tekkadon, you should not pour soy sauce over the bowl, but instead dip "sashimi" of maguro in soy sauce from a small dish.