What is going on in this crazy house?

Mama and Daddy keep wrapping up boxes and putting them under the tree. What's up with that? What's in those boxes? Why are they being crazy? First this big tree shows up, then there's all this green and red stuff with snowmen and this crazy guy in red all over it, then they hang socks above our fireplace (socks, for crying out loud!), and now these wrapped up boxes!?! And the other night I swear I heard them putting together some big, loud toy but now it's nowhere to be seen. This whole "Christmas" thing is weird. I don't get it.