Hibachi is used in the u.S. as a term for japanese teppanyaki cooking, in which gas-heated hotplates are integrated into tables around which many people (often multiple parties) can sit & eat at once. The chef performs the cooking in front of the diners, typically w/ theatrical flair—such as lighting a volcano-shaped stack of raw onion hoops on fire.
Sushi & Sashimi
Sushi is cooked vinegared rice which is commonly topped w/ other ingredients, such as fish or other seafood[1], or put into rolls.
Sashimi
Is a japanese delicacy primarily consisting of very fresh raw seafood, sliced into thin pieces & served w/ only a dipping sauce (soy sauce w/ wasabi paste or other condiments such as grated fresh ginger, or ponzu).