Today, September 18th, is National Cheeseburger Day.
The base of the cheeseburger is, of course, a hamburger. The name hamburger originates from the German city of Hamburg, although it likely didn't originate there.
The hamburger is a ground meat, usually beef leading to the other common name of the beefburger, patty which is then placed between a sliced bun - a type of sandwich in other words.
A cheeseburger has cheese added to this. This is usually a slice of processed cheese on top of the burger, but it is done in other ways too, including having the cheese cooked inside the burger itself.
The cheeseburger is associated with fast food and poor nutritional food, but it is perfectly possible to prepare one from scratch that is healthy to eat. This is quite a lot slower than going to a fast food restaurant though.
Image: By Renee Comet (photographer) [Public domain], via Wikimedia Commons