Sushi refered to as picled fish preserved in venegar. it was then innovated and become popular dish in japan that is serve in every occasional event.
here is some different examples of famous Sushi in Japan:
Nigiri- small rice balls with fish, shellfish on top.
Gunkan- Sushi rice and dried seaweed filled with seafood.
Norimaki- Sushi rice and seafood, rolled in dried seaweed sheets.
Temaki- Temakizushi are cones made of nori seaweed and filled with sushi rice and vegetables.
Oshizushi- pressed sushi, inwhich the fish pressed onto the sushi rice in a wooden box.
Inari- simple inexpensive f type, sushi is filled into aburaage bags.
Chirashi- seafood, mushrooms and vegetables are spread over sushi rice.