And so if we're doing it as a Venn diagram, the universe is usually depicted as some type of a rectangle right over here. And it itself is a set and it usually is denoted with the capital U, U for universe, not to be confused with the union set notation. And you could say that the universe is all possible things that could be in a set, including farm animals and kitchen utensils and emotions and types of Italian food or even types of food. But then that just becomes somewhat crazy because you're literally thinking of all possible things. Normally when people talk about a universal set, they're talking about a universe of things that they care about. So the set of all people or the set of all real numbers or the set of all countries, whatever the discussion is being focused on. But we'll talk about an abstract terms right now.