There are all kinds of different things to know, including both knowledge that something is the case and knowledge how to do something, but not every knowable thing is of equal importance; there are things that one must know to be a smart person and then there is a shit ton of things that reveal nothing interesting about the person that either does or does not know them.
A good way to figure out what stuff falls into the category of things you need to know to be smart ("smart people knowledge") is to ask, "Is this the kind of knowledge that might be placed at the end of the sentence, 'Americans are very stupid because they don't know...'" This phrase is the universal marker of things that do not have anything to do with how smart a person is. This category is filled with the kinds of things you might be taught by an uninspired high school history teacher: the names of the Presidents, state capitals, the year of Magna Carta, etc.
But it is not just uninspired high school history teachers; every year at least one or two of the people who obtain a PhD in History from Harvard have done so simply by amassing a huge quantity of knowledge, not one iota of which that counts as smart people knowledge. Now, it is only one or two because, while the subject of history theses is rarely important, the act of producing that document usually reveals a great deal that is important to know.
What are some things that are definitely in the smart people knowledge category? Evolution. If you don't understand evolution, you are stupid, no matter what your IQ.
Not only does lacking this understanding prevent a person from knowing the first thing about biology, it also renders a person helpless in the face of every topic of human understanding where smart people explain themselves using natural selection as a metaphor. And when you think about the set of things that smart people care about, it is more or less co-extensive with the set of things that smart people sometimes explain using natural selection as a metaphor. In the remainder of things natural selection is not a metaphor, it is literally the process driving the subject (e.g., cultural change over time).