Some people don't know mcdonalds had to rechristen their business for hamburgers.
What do you mean by "rechristen their business"? Sort of an odd choice of words haha
they were not a hamburger stand at first, it was hot dogs. 
I didn't know that! How did the hamburger become their flagship item?
possibly because they saw the popularity. They are popular for their hamburgers.But also fries and milkshakes 
What else can you tell me about McDonalds? I thought there was some backstory haha
in 1940 Richard and Marice McDonald founded the resturant in San Bernardino. 
Was it a restaurant like the McDonalds we see today or was it different?
Not like you know today. It didn't have golden arches until 1953
Was it a sit down restaurant at some point or were they always fast food?