When most people think of sushi they think of RAW fish. This is not correct. Actually if you go into any sushi bar and look at all the seafood choices, only a small handful will be actually raw. Most fish has been prepared in some fashion. Even though it might look raw, it has gone through some kind of process. Either pickled, blanched, soaked in Sake (rice wine) and then frozen, there are many things that happen to the fish before you eat it.