Washoku is traditional Japanese cuisine, which referes to individual Japanese food or set of Japanese dishes.
Washoku was designated as UNESCO Intangeble Cultural Heritage in 2013.
Washoku is characterized be the use of various seasonal fresh foods.
Washoku is famous as very healthy food, because it's a low calorie, nutritious and well-balanced diet.
Washoku is mainly divided into informal and formal.
Informal washoku includes sushi, tempura, or deep-fried fish and vegetables, and yakitori, or skewered grilled chicken.
Formal washoku are Kaiseki-ryori, or tea ceremony dishes; another Kaiseki-ryori, or course meals for traditional parties; and Honzen-ryori, or course meals for ceremonial functions; and Shojin-ryori, or vegetarian dishes.
I strongly recommend you try authentic Japanese cuisine during you stay in Japan.