I have noticed that often people use the terms "sushi" and "sashimi" interchangeably, but in reality, the meanings are quite different.
Sashimi always includes thinly sliced seafood such as tuna or salmon that is not served with rice.
Sushi describes rice with vinegar that is mixed with other ingredients which may or may not include raw fish.
Arriving at the perfect mixture of rice and vinegar is a true art form and people will pay hundreds of dollars per meal at a designated hot spot as well as waiting months for a reservation.