I'm on my second week of Calculus, and I still cannot seem to grasp what a limit is and what exactly it does. I've tried getting help, but most tutors don't seem to understand it, and the ones who do are almost never available.
Why are they structured as
x --> 2
lim tan ((piX)/4)
x --> 3
why are do the x --> c sometimes have the c's: c- or c+?
Basically, what is the point and why are they structured the way they are. I know this is a lot to ask all at once, but I feel I have exhausted all the rather poor resources I have available.