The simplest way to think of infinity is the same way as a variable. Let's say infinity = x. There are x numbers between 0 and 1, and 1 and 2, and so on. There are x^x real numbers because of this. This also says that, in a 3D graph, there are x^(x^x) combinations, as a 3D graph doesn't have an infinite length. Otherwise, it would have been x^(x^(x^x)).