Hotdog is sausage, especially one served hot in a long, soft roll and topped with various condiments. The sausages used for the dish are Wiener (Vienna sausage) or a Frankfurter (Frankfurter Würstchen, also just called frank).
These types of sausages were culturally imported from Germany and became popular in the United States. It became a working-class street food in the U.S., sold at stands and carts. The hot dog became closely associated with baseball and American culture. Although particularly connected with New York City and its cuisine, the hot dog eventually became ubiquitous throughout the US during the 20th century. Its preparation varies regionally in the country, emerging as an important part of other regional cuisines, including Chicago street cuisine.
Frankfurt-am-Main, Germany, is traditionally credited with originating the Frankfurter. However, this claim is disputed by those who assert that the popular sausage - known as a "dachshund" or "little-dog" sausage - was created in the late 1600's by Johann Georghehner, a butcher, living in Coburg, Germany. According to this report, Georghehner later traveled to Frankfurt to promote his new product.