Think of fishballs as the equivalent of meatballs. Just substitute your beef/pork/chicken with fish. The same way meatballs are made with mystery meat some times, fishballs are made with mystery fish. It’s all pulverized so it really doesn’t matter as much.
Fishballs are served in several ways. The most popular is fishballs in noodle soups. Then there are curry fishballs on skewers, fishballs in soups, steamed fishballs as dimsums, grilled fishballs, stirfry veggies with fishballs… you name it.
Better fishballs are fishy, smooth, tender almost to a paste.
Where to get this in NYC: For curry fishballs, best place I’ve had is at Hong Kong Station in Chinatown. Fishballs in soups you can find in Vietnamese restaurants sometimes, and Chiu Chow restaurants.
Fishballs aren’t bad. But the ones you get in the frozen section have the texture (elasticity) of a bouncy ball.