If you haven't already belted out the chorus to Mariah Carey's "All I Want For Christmas Is You," then you aren't properly preparing for the holiday season. (If you need inspiration, check out the Queen herself coaching her kids through the chorus. ) No matter what you're celebrating, where you're celebrating, or whom you're celebrating with, no seasonal gathering is complete without at least one solid holiday music jam session. Due to the essential nature of such songs, we've rounded up the best, most singable, and most heartwarming ones for you.