Little credit card help?

Now i was looking at some info on this Sam's club discover credit i got....because it saved me an $40 on a A/c unit. Basically I just wanna make sure I'm correct on something here. It says current variable purchase APR...now if I remember right that means Anual Percentage Rate but....what I wanna know is for paying a statement say you don't pay it or pay the minimum amount is this APR the interest that will be added on top of the remaining balance for your next statement? That's basically all I wanted to know...last time I talked about credit cards was about a year or so more so I'm a little rusty.