Welcome to the final chapter, Limits. Well you could say it’s the final precalculus chapter—or you could call it the first chapter of calculus. Like it or not, all of calculus is built on limits. Better still, the applications for it are everywhere. Literally. This makes this chapter the most important chapter you've ever studied in any subject, ever.
Okay, maybe not quite. But it does make perfect sense to get limits down now so you don't have to worry about them when they inevitably come back to haunt you later.