In the UK (and lots of other commonwealth countries) we celebrate boxing day, as far as I can remember its always been the 26th December.
It has something to do with tradesmen and servants getting a Christmas box, to us here in the UK its a bank holiday.
It is also St Stephen’s day and there seems to be links between St Stephen and giving gifts to the “lower classes”
In the olden days Boxing Day for us was our sale day, a bit like Black Friday in the States. Of course now, we also seem to have a Black Friday.
There you go a bit of a history lesson. You are all most welcome