Hamburger "patty" is rarely used, or the term can even refer simply to ground beef. The term may be prefixed with the type of meat or meat substitute used, as in "turkey burger", "bison burger", or "veggie burger". Hamburgers are sold at fast-food restaurants, diners, and specialty and high-end restaurants (where burgers may sell for several times the cost of a fast-food burger, but may be one of the cheaper options on the menu). There are many international and regional variations of the hamburger. The term "hamburger" originally derives from Hamburg, Germany's second-largest city. In German, "Burg" means "castle", "fortified settlement"
Hamburger eaten by many emigrants on their way to America, but may have contained roasted beefsteak rather than Frikadeller. Hamburg steak is reported to have been served between two pieces of bread on the Hamburg America Line, which began operations in 1847. Each of these may mark the invention of the Hamburger, and explain the name. There is a reference to a "Hamburg steak" as early as 1884 in the Boston Journal. On July 5, 1896, the "Chicago Daily Tribune" made a highly specific claim regarding a "hamburger sandwich" in an article about a "Sandwich Car": "A distinguished favorite, only five