So once again, it has very fancy notation, but it's just saying, look, what is the function approaching as x gets closer and closer to 1? Let me do another example where we're dealing with a curve, just so that you have the general idea. So let's say that I have the function f of x, and let me just, just for the sake of variety, let me call it g of x. Let's say that we have g of x is equal to, I could define it this way, we could define it as x squared when x does not equal, I don't know, when x does not equal 2, and let's say that when x equals 2, when x equals 2, it is equal to 1. So once again, a kind of an interesting function that, as you'll see, is not fully continuous. It has a discontinuity. Let me graph it.