What IS the difference between a "hot DOG" and a "HOT dog?""

German immigrants brought the food to New York in the 1860s, where street vendors sold them as “dachshund sausages,” presumably because of their shape. It is from this that the term hot dog derives, with the implied suggestion that the sausage really was made of dog flesh. The first attestation of the phrase used in that sense dates to 1884, and by 1892 it was in widespread usage around the United States.