I know it's bad but my guilty pleasure is McDonalds
I would have to agree with you on that, I love McDonald's food! I wonder how long they've been around for.
It was founded in 1940 by Richard and Maurice McDonal
Oh wow, so it's been around for a while and it's still a pretty big franchise!  What else can you tell me about McDonald's?
They started their first restaurant in in San Bernardino, California. all the good stuff starts there.
Did they make it big right away, or was there some struggle to get where they are today?
Before it became the big arches they rechristened their business as a hamburger stand.
Are they the biggest fast food chain of modern times? It seems like they would be, but I'm not really sure.
It sure is! it serves over 69 million customers daily 
Holy cow that's a lot! You have any idea how many stores they operate world wide?
Yes its found in 100 countries across approximately 36,900 outlets as of 2016