That right there is a set. I could have another set. Let's call that set y. I didn't have to call it y. I could have called it a. I could have called it sal. I could have called it a bunch of different things, but I'll just call it y. And let's say that set y, it's a collection of the distinct objects, the number 14, the number 15, the number 6, and the number 3. So fair enough. Those are just two set definitions.