Where exactly the Singleton Pattern is used in real application?

Question

I was just curious where exactly the singleton pattern is used... I know how the pattern works and where it can be used but i personally never used in any real application. Can

Answer 1

I used the singleton pattern in an online Football Team Store System. we applied the singleton pattern to a ShoppingCart class.

You only needed one instance of the cart per an application instance. so the singleton seemed like it's the best fit for that situation.