Bialy is a small roll named for the city of Bialystok, Poland. A traditional bialy has a diameter of up to 15 cm (6 inches) and is a chewy yeast roll similar to a bagel. Unlike a bagel, a bialy is not boiled, rather it is simply baked (bagels are boiled before baking), and instead of a hole in the middle it has a depression. Before baking, this depression is filled with diced onions and other ingredients including (depending on the recipe) garlic, poppy seeds, or bread crumbs.

The name bialy is short for bialystoker kuchen (Bialystok's Cake). The bialy is little known outside of New York City, where it was originally brought into the United States by Ashkenazi Jewish immigrants during the late 19th century and early 20th century.
The bialy was first marketed in the United States during the early 1900's in the state of New York by Harry Cohen, a proprietor of a Bagel (and later bialy) establishment.