The Use of Infinity in Mathematical Calculus

In a calculus class it's a useful symbol for for doing certain calculations talking about how function behaves as the input becomes very large. That's a notion of infinity that's kind of in the first sense where you kind of view infinity as an idealized point at the end of the line. You can also talk about counting the number of elements of some collection or some set and keeping track of either you know how many finitely many elements it has or maybe if it has infinitely many elements trying to distinguish maybe between different sizes of infinity.