Many non-Japanese do not know the difference between sushi and sashimi. Usually these people think that sushi always contains raw fish but it is not true. The fact is that sushi must contain rice and rice vinegar and sugar must be contained in the rice.
On the other hand, sashimi never contains rice and usually raw fresh fish are used. Sushi can be bought at convenience stores which are opened 24 hours, all year around but it is very rare to find sashimi at these stores.
Sashimi is very popular dish at Izakaya style restaurants in Japan. Izakaya can be refered as Japanese tavern or pubs, where yu can drink alcohol and eat small dishes at the same time. Then, these izakaya offer "sashimi no moriawase" which is assortment of sashimi, usually three or more kinds of raw fresh fish to be served. Then, please note that no one orders steam rice together at the izakaya.