There are 6 per year: New Years, Memorial Day, 4th of July, Labor Day, Thanksgiving, Christmas
I am not 100% on this, but I believe it works like benefits, in that you are eligible after 6 months. You don't necessarily get a full 8 hours of pay though. It is based on the average number of hours you work a week, kind of like the way vacation works.
this one gets our store every year because theres always one of the TLs or ETLs who thinks its a time and a half holiday therefore we can work sat night into sun morning plus 5 days that week and not get OT
The good news is that anyone working on the listed holidays gets time and a half pay for hours work that day. So, even if you don't qualify for a full paid day, you still get some extra cash for doing the same job.
If it's a religious holiday, enough to close the store (like Thanksgiving and Christmas), obviously, they should pay time-and-a-half for those people who have to come into work. If they're not going to pay that, they might as well as have the store open on Easter day.