Said as an expression to signify when there is indeed a difference between two things or situations, but that difference is unimportant or negligible. Often used when someone is making a big deal out of an
insignificant difference. Can also be used to indicate indifference between two choices.
Origin of the phrase: Generally, if someone wants a
cheeseburger, and they're served a hamburger, they won't fuss or complain. Sure, there's a difference, but who cares? It's a
slice of cheese. Your life's not going to end because you didn't get cheese. Get over it.