The name red hots for hot dogs came from a saying in 1901 at the New York Polo Grounds on a cold April day.
On that day hot dog vendors were hawking or selling hot dogs from portable hot water tanks and were saying they are red hot.
So that's where the name red hots came from for hot dogs.
I remember hearing on Sesame Street with Grover and Fat Blue at a ball game where one of the muppets on their was saying get your red hots.
That's where I first heard the saying but wasn't sure where the name came from.
That is until I did some research and came to find out the reason the hot dogs were called or are called red hots.