A hot dog bun is a type of soft bun shaped specifically to contain a hot dog or another sausage.
The familiar American side-loading bun is a long roll split lengthwise, creating a cradle for the sausage and its toppings. A related top-loading style, often called a New England-style bun, has flat sides and an opening cut into the top.
The bun’s history is connected with late-19th-century American street food. Charles Feltman is often credited with developing an elongated bun for serving hot dogs on Coney Island in 1871, while another account links the design to baker Ignatz Frischmann’s Vienna roll. A separate story places an important development at the 1904 Louisiana Purchase Exposition.
A pita is a pocket bread, a Kaiser roll is a crusty round roll, and a hamburger bun is designed to encase a patty. They can hold sausages in some dishes, but none is the canonical name for this purpose-built bun.