UX vs UI – It’s like a restaurant

It’s like a restaurant.

The utensils, plate, table, chair, that’s user interface (which can contribute to experience).
The food, service, ambience, that’s user experience. – Chrys Bader, Co-Founder of Secret Suggest Bio

Update: To put it very simply: The UI is what people use to interact with your product, and the UX is how they feel while they do.