And that makes sense. This graph is going to look something like, we have a slope of one, so it's going to look something like this. And then right when x is equal to one and the value of our function is zero, it looks something like this. It looks something like this. And so the graph is continuous. The graph for sure is continuous, but our slope coming into that point is one and our slope right when we leave that point is zero. So it is not differentiable over there.