sushi - raw fish on top of sticky rice. sometimes the wasabi is already added to the mix.
sashimi - no rice, just the raw fish.
Only rolls (whether they're maki or hand) have seaweed. even the california ones, mr. furious. California rolls are basically rolled with the rice is on the outside, and the seaweed inside - plus sesame seeds. What makes them *california* is the addition of avocado and crab.